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Hadron colliders offer a unique opportunity to test perturbative QCD because, rather than producing events at a specific beam energy, the dynamics of the hard scattering is probed simultaneously at a wide range of momentum transfers. This makes the determination of $\al$ and the parton density functions (PDF) at hadron colliders particularly interesting. In this paper we restrict ourselves to extracting $\al$ for a given PDF at a scale which is directly related to the transverse energy produced in the collision. As an example, we focus on the single jet inclusive transverse energy distribution and use the published '88-'89 CDF data with an integrated luminosity of 4.2 pb$^{-1}$. The evolution of the coupling constant over a wide range of scales (from 30~GeV to 500~GeV) is clearly shown and is in agreement with the QCD expectation. The data to be obtained in the current Tevatron run (expected to be well in excess 100 pb$^{-1}$ for both the CDF and D\O\ experiments) will significantly decrease the experimental errors. | A bstractWe use the antenna subtraction method to isolate the double virtual infrared singularities present in gluonic scattering amplitudes at next-to-next-to-leading order. In previous papers, we derived the subtraction terms that rendered (a) the double real radiation tree-level process finite in the single and double unresolved regions of phase space and (b) the mixed single real radiation one-loop process both finite and well behaved in the unresolved regions of phase space. Here, we show how to construct the double virtual subtraction term using antenna functions with both initial- and final-state partons which remove the explicit infrared poles present in the two-loop amplitude. As an explicit example, we write down the subtraction term for the four-gluon two-loop process. The infrared poles are explicitly and locally cancelled in all regions of phase space leaving a finite remainder that can be safely evaluated numerically in four-dimensions. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 26,500 |
We determine the uncertainties on observables arising from the errors on the experimental data that are fitted in the global MRST2001 parton analysis. By diagonalizing the error matrix we produce sets of partons suitable for use within the framework of linear propagation of errors, which is the most convenient method for calculating the uncertainties. Despite the potential limitations of this approach we find that it can be made to work well in practice. This is confirmed by our alternative approach of using the more rigorous Lagrange multiplier method to determine the errors on physical quantities directly. As particular examples we determine the uncertainties on the predictions of the charged-current deep-inelastic structure functions, on the cross-sections for W production and for Higgs boson production via gluon-gluon fusion at the Tevatron and the LHC, on the ratio of W- to W+ production at the LHC and on the moments of the non-singlet quark distributions. We discuss the corresponding uncertainties on the parton distributions in the relevant x,Q2 domains. Finally, we briefly look at uncertainties related to the fit procedure, stressing their importance and using \(\sigma_W\), \(\sigma_H\) and extractions of \(\alpha_S(M_Z^2)\) as examples. As a by-product of this last point we present a slightly updated set of parton distributions, MRST2002. | We investigate the theoretical description of the central exclusive production process, $h_1 + h_2 \to h_1+X+h_2$. Taking Higgs production as an example, we compute the subset of next-to-leading order corrections sensitive to the Sudakov factor appearing in the process. Our results agree with those originally presented by Khoze, Martin and Ryskin except that the scale appearing in the Sudakov factor, $\mu=0.62 \sqrt{\hat{s}}$, should be replaced with $\mu=\sqrt{\hat{s}}$, where $\sqrt{\hat{s}}$ is the invariant mass of the centrally produced system. We show that the replacement leads to approximately a factor 2 suppression in the cross-section for central system masses in the range 100--500GeV. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 26,501 |
Many surgical methods have been developed for reconstruction of extensive defects resulting from resection of lower lip cancer, with the aim of achieving of normal appearance and function. However, observers' subjective evaluation, which is the method usually employed, makes comparison of the outcomes of appearance and function obtained from different techniques difficult. In this paper, a speech intelligibility test and electromyography were used as objective means of evaluating the motor function of the reconstructed lower lip. | Background ::: Reconstruction of the lip defects following wide excision of the squamous cell cancer is challenging for the surgeon. Our aim was to define the role of the inferiorly based nasolabial flap for lip reconstruction in such cases with moderate to large size defects. | A future lepton collider, such as the proposed CLIC or ILC, would allow to study top quark properties with unprecedented precision. In this paper, we present a method to reconstruct the $t \bar{t}$ decay in the dilepton channel at future $e^+e^-$ colliders. We derive a simple, closed analytical expression for the neutrino four-momenta as a function of the $W$ boson mass and develop a maximization procedure to find the optimal solution for the reconstruction of the full $t \bar{t}$ event. We show that our method is able to reconstruct neutrino four-momenta with an error of less than $2 \, \%$ in $60 \, \%$ of the times. Finally, we test the performance of this reconstruction method in the calculation of the helicity fractions of the $W$ boson. A precise measurement of these observables could be used to probe new physics effects in the $Wtb$ vertex. We find that, from a large $t \bar{t}$ sample, our reconstruction method allows to calculate these observables with an accuracy better than $1 \, \%$. | eng_Latn | 26,502 |
Two experiments of four-photon interference are performed with two pairs of photons from parametric downconversion with the help of asymmetric beam splitters. The first experiment is a generalization of the Hong-Ou-Mandel interference effect to two pairs of photons while the second one utilizes this effect to demonstrate a four-photon de Broglie wavelength of λ/4 by projection measurement. | It is widely believed that quantum gravity effects are negligible in a conventional laboratory experiment because quantum gravity should play its role only at a distance of about Planck's length ($\sim10^{-33}$ cm). Sometimes that is not the case as shown in this article. We discuss two new ideas about quantum physics connections with gravity. First, the Hong-Ou-Mandel effect relation to quantum gravity is examined. Second, it is shown that the very existence of gravitons is a consequence of quantum statistics. Moreover, since the Bose-Einstein statistics is a special case of Compound Poisson Distribution, it predicts the existence of an infinite family of high-spin massless particles. | In this paper administrative data from the unemployment-insurance (UI) system are used to examine the distribution of unemployment spells. Hazard plots of the data reveal a strong clustering around the benefit exhaustion point. In addition, estimation of the effects of the exhaustion point and of the UI benefit level on spell lengths obtained with a non-parametric proportional-hazards model - estimated by direct maximization of the general likelihood function - shows significant effects of both. However, the effect of the exhaustion point on the hazard is not proportional, making detection of its effect somewhat difficult. | eng_Latn | 26,503 |
We present a supersymmetric see-saw $S_4$ model giving rise to the most general neutrino mass matrix compatible with Tri-Bimaximal mixing. We adopt the $S_4\times Z_5$ flavour symmetry, broken by suitable vacuum expectation values of a small number of flavon fields. We show that the vacuum alignment is a natural solution of the most general superpotential allowed by the flavour symmetry, without introducing any soft breaking terms. In the charged lepton sector, mass hierarchies are controlled by the spontaneous breaking of the flavour symmetry caused by the vevs of one doublet and one triplet flavon fields instead of using the Froggatt-Nielsen U(1) mechanism. The next to leading order corrections to both charged lepton mass matrix and flavon vevs generate corrections to the mixing angles as large as ${\cal O}(\lambda_C^2)$. Applied to the quark sector, the symmetry group $S_4\times Z_5$ can give a leading order $V_{CKM}$ proportional to the identity as well as a matrix with ${\cal O}(1)$ coefficients in the Cabibbo $2\times 2$ submatrix. Higher order corrections produce non vanishing entries in the other $V_{CKM}$ entries which are generically of ${\cal O}(\lambda_C^2)$. | Discrete flavour groups have been studied in connection with special patterns of neutrino mixing suggested by the data, such as Tri-Bimaximal mixing (groups A4, S4...) or Bi-Maximal mixing (group S4...) etc. We review the predictions for sin(\theta_13) in a number of these models and confront them with the experimental measurements. We compare the performances of the different classes of models in this respect. We then consider, in a supersymmetric framework, the important implications of these flavour symmetries on lepton flavour violating processes, like \mu ->e gamma and similar processes. We discuss how the existing limits constrain these models, once their parameters are adjusted so as to optimize the agreement with the measured values of the mixing angles. In the simplified CMSSM context, adopted here just for indicative purposes, the small tan(beta) range and heavy SUSY mass scales are favoured by lepton flavour violating processes, which makes it even more difficult to reproduce the reported muon g-2 discrepancy. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 26,504 |
The basic structure of top-quarks as spin-1/2 particles is characterized by the radius R t and the intrinsic magnetic dipole moment κ t , both individually associated with gauge interactions. They are predicted to be zero in pointlike theories as the Standard Model. We derive upper limits of these parameters in the color sector from cross sections measured at Tevatron and LHC in top pair production p p ¯ / p p → t t ¯ , and we predict improved limits expected from LHC in the future, especially for analyses exploiting boosted top final states. An additional method for measuring the intrinsic parameters is based on t t ¯ + j e t final states. | A bstractWe consider top-antitop quark (tt¯$$ t\overline{t} $$) production at the Large Hadron Collider (LHC) with subsequent decay into dileptonic and lepton plus jets final states. We present a set of leptonic angular correlations and distributions with which experiments can probe all the independent coefficient functions of the top-spin dependent parts of the tt¯$$ t\overline{t} $$ production spin density matrices. We compute these angular correlations and distributions for LHC center-of-mass energies 8, 13, and 14 TeV within the Standard Model at next-to-leading order in the QCD coupling including the mixed QCD-weak corrections and for the transverse top-quark polarization and the tt¯$$ t\overline{t} $$ charge asymmetry also the mixed QCD-QED corrections. In addition we analyze and compute the effects of new interactions on these observables in terms of a gauge-invariant effective Lagrangian that contains all operators relevant for hadronic tt¯$$ t\overline{t} $$ production up to mass dimension six. | The oxidative polymorphism of debrisoquine (DBQ) has been determined in 89 patients with colo-rectal cancer and in 556 normal control subjects. Four patients and 34 controls, with a metabolic ratio >12.6, were classified as poor metabolisers of DBQ (n.s.). | eng_Latn | 26,505 |
Excellent energy resolution is one of the primary advantages of electroluminescent high-pressure xenon TPCs. These detectors are promising tools in searching for rare physics events, such as neutrinoless double-beta decay (ββ0ν), which require precise energy measurements. Using the NEXT-White detector, developed by the NEXT (Neutrino Experiment with a Xenon TPC) collaboration, we show for the first time that an energy resolution of 1% FWHM can be achieved at 2.6 MeV, establishing the present technology as the one with the best energy resolution of all xenon detectors for ββ0ν searches. | NEXT (Neutrino Experiment with a Xenon TPC) is an experimental program whose goals are to discover neutrinoless double beta decay using $^{136}$Xe in high pressure xenon TPCs with electroluminescent readout. In this paper, results from the NEXT-White detector, which is currently taking data at Laboratorio Subterr\'aneo de Canfranc (LSC) will be reported. The prospects for the NEXT-100 apparatus, scheduled to start operations in 2020, as well as the plans to extend the technology to large and ultra-low background detectors needed to fully explore the inverse hierarchy of neutrino masses, will also be briefly discussed. | NEXT (Neutrino Experiment with a Xenon TPC) is an experimental program whose goals are to discover neutrinoless double beta decay using $^{136}$Xe in high pressure xenon TPCs with electroluminescent readout. In this paper, results from the NEXT-White detector, which is currently taking data at Laboratorio Subterr\'aneo de Canfranc (LSC) will be reported. The prospects for the NEXT-100 apparatus, scheduled to start operations in 2020, as well as the plans to extend the technology to large and ultra-low background detectors needed to fully explore the inverse hierarchy of neutrino masses, will also be briefly discussed. | eng_Latn | 26,506 |
Response of coumarin in aqueous solution has been studied earlier for gamma rays and fast neutrons by fluorescence measurement. For further fast neutron studies, two systems viz. coumarin in H 2 O and coumarin in D 2 O, were irradiated with fast neutrons in snif facility in the swimming pool type apsara reactor at Trombay. Neutron fluence was estimated by measuring induced activity in sulphur pellet and associated gamma radiation was estimated using CaSO 4 :Dy TLD powder. The kerma values were calculated for H 2 O and D 2 O, assuming modified fission spectrum for fast neutron in snif position, and they were in the ratio of 2:1. Response of a chemical dosimetric system is expected to be proportional to the absorbed dose in the respective system for the same neutron fluence. This was experimentally found to be the case for coumarin in H 2 O or D 2 O. These results are likely to be true in general for any aqueous chemical system. The limitations of using such a dual system for dosimetry in a mixed field is discussed. | Evaluation of the characteristics of accelerator-based thermal neutron fields is recognized as an important issue when discussing the effectiveness of boron neutron capture therapy (BNCT). In this ... | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 26,507 |
In light of G\"{o}del's undecidability results (incomplete theorems) for math, quantum indeterminism indicates that physics and the Universe may be indeterministic, incomplete, and open in nature, and therefore demand no single unification theory of everything. The Universe is dynamic and so are the underlying physical models and spacetime. As the 4-d spacetime evolves dimension by dimension in the early universe, consistent yet different models emerge one by one with different sets of particles and interactions. A new set of first principles are proposed for building such models with new understanding of supersymmetry, mirror symmetry, and the dynamic phase transition mechanism - spontaneous symmetry breaking. Under this framework, we demonstrate that different models with no theory of everything operate in a hierarchical yet consistent way at different phases or scenarios of the Universe. In particular, the arrow of time is naturally explained and the Standard Model of physics is elegantly extended to time zero of the Universe. | Baryon asymmetry of the universe (BAU) is naturally explained with $K^0-K^{0'}$ oscillations of a newly developed mirror-matter model and new understanding of quantum chromodynamics (QCD) phase transitions. A consistent picture for the origin of both BAU and dark matter is presented with the aid of $n-n'$ oscillations of the new model. The global symmetry breaking transitions in QCD are proposed to be staged depending on condensation temperatures of strange, charm, bottom, and top quarks in the early universe. The long-standing BAU puzzle can then be understood with $K^0-K^{0'}$ oscillations that occur at the stage of strange quark condensation and baryon number violation via a non-perturbative sphaleron-like (coined "quarkiton") process. Similar processes at charm, bottom, and top quark condensation stages are also discussed including an interesting idea for top quark condensation to break both the QCD global $U_t(1)_A$ symmetry and the electroweak gauge symmetry at the same time. Meanwhile, the $U(1)_A$ or strong CP problem of particle physics is simply solved under the same framework. | We review the unified description of massless spinning particles, living in spaces of constant curvature, in the framework of the pseudoclassical approach with a gauged $N$-extended worldline supersymmetry and a local $O(N)$ invariance. | eng_Latn | 26,508 |
Extraction of the strange quark PDF is a long-standing puzzle. We use the nCTEQ nPDFs with uncertainties to study the impact of the LHC W/Z production data on both the flavor differentiation and nuclear corrections; this complements the information from neutrino-DIS data. As the proton flavor determination is dependent on nuclear corrections (from heavy target DIS, for example), LHC heavy ion measurements can also help improve proton PDFs. We introduce a new implementation of the nCTEQ code (nCTEQ++) based on C++ which has a modular strucure and enables us to easily integrate programs such as HOPPET, APPLgrid, and MCFM. Using ApplGrids generated from MCFM, we use nCTEQ++ to perform a preliminary fit including the pPb LHC W/Z vector boson data. | We present a first determination of the nuclear parton distribution functions (nPDF) based on the NNPDF methodology: nNNPDF1.0. This analysis is based on neutral-current deep-inelastic structure function data and is performed up to NNLO in QCD calculations with heavy quark mass effects. For the first time in the NNPDF fits, the \(\chi ^2\) minimization is achieved using stochastic gradient descent with reverse-mode automatic differentiation (backpropagation). We validate the robustness of the fitting methodology through closure tests, assess the perturbative stability of the resulting nPDFs, and compare them with other recent analyses. The nNNPDF1.0 distributions satisfy the boundary condition whereby the NNPDF3.1 proton PDF central values and uncertainties are reproduced at \(A=1\), which introduces important constraints particularly for low-A nuclei. We also investigate the information that would be provided by an Electron-Ion Collider (EIC), finding that EIC measurements would significantly constrain the nPDFs down to \(x\simeq 5\times 10^{-4}\). Our results represent the first-ever nPDF determination obtained using a Monte Carlo methodology consistent with that of state-of-the-art proton PDF fits, and provide the foundation for a subsequent global nPDF analyses including also proton-nucleus data. | ABSTRACTUNC-45A is an ubiquitously expressed protein highly conserved throughout evolution. Most of what we currently know about UNC-45A pertains to its role as a regulator of the actomyosin system... | eng_Latn | 26,509 |
The leading-twist valence-quark distribution function in the pion is obtained at a low normalization scale of an order of the inverse average size of an instanton r c . The momentum dependent quark mass and the quark-pion vertex are constructed in the framework of the instanton liquid model, using a gauge invariant approach. The parameters of instanton vacuum, the effective instanton radius and quark mass, are related to the vacuum expectation values of the lowest dimension quark-gluon operators and to the pion low energy observables. An analytic expression for the quark distribution function in the pion for a general vertex function is derived. The results are QCD evolved to higher momentum-transfer values, and reasonable agreement with phenomenological analyses of the data on parton distributions for the pion is found. | After a general discussion on the choice of gauge, we compare the quark propagator in the background of one instanton in regular and singular gauge with a gauge invariant propagator obtained by inserting a path-ordered gluon exponential. Using a gauge motivated by this analysis, we were able to obtain a finite result for the quark condensate without introducing an infrared cutoff nor invoking some instanton model. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 26,510 |
A high precision calibration of the nonlinearity in the energy response of the Daya Bay Reactor Neutrino Experiment’s antineutrino detectors is presented in detail. The energy nonlinearity originates from the particle-dependent light yield of the scintillator and charge-dependent electronics response. The nonlinearity model is constrained by γ calibration points from deployed and naturally occurring radioactive sources, the β spectrum from ^(12)B decays, and a direct measurement of the electronics nonlinearity with a new flash analog-to-digital converter readout system. Less than 0.5% uncertainty in the energy nonlinearity calibration is achieved for positrons of kinetic energies greater than 1 MeV. | The RENO experiment has observed the disappearance of reactor electron antineutrinos, consistent with neutrino oscillations, with a significance of 4.9 standard deviations. Antineutrinos from six 2.8 GW(th) reactors at the Yonggwang Nuclear Power Plant in Korea, are detected by two identical detectors located at 294 and 1383 m, respectively, from the reactor array center. In the 229 d data-taking period between 11 August 2011 and 26 March 2012, the far (near) detector observed 17102 (154088) electron antineutrino candidate events with a background fraction of 5.5% (2.7%). The ratio of observed to expected numbers of antineutrinos in the far detector is 0.920±0.009(stat)±0.014(syst). From this deficit, we determine sin(2)2θ(13)=0.113±0.013(stat)±0.019(syst) based on a rate-only analysis. | Stability, nonnegativity, and initial conditions are examined in two closed two-compartment models with time-delay proposed by Cobelli and Rescigno [1] and Bellman [2]. | eng_Latn | 26,511 |
Our previous study showed that deep white matter lesions (DWML) were associated with subtle cognitive decline in community-dwelling elderly people. However, even extensive (EXT)-DWML, found in 7 (4%) of 178 subjects aged 60 years or older, did not cause dementia. The purpose of the present study was to investigate brain circulation in nondemented elderly subjects with EXT-DWML. We compared cerebral blood flow in the deep white matter and frontal cortex between 5 subjects with EXT-DWML and 5 without such lesions, using a xenon-enhanced computed tomography (CT) method. Although the difference of deep white matter findings on magnetic resonance imaging (MRI) was the greatest possible (i.e., extensive v no or minimum lesions), cerebral blood flow values in anterior deep white matter and frontal cortex were 21.4 ± 5.3 standard deviation (SD) mL/100 g/minute and 42.7 ± 4.1, respectively, in subjects with extensive lesions, which were not significantly different from 24.3 ± 4.3 and 44.0 ± 7.1 in subjects without DWML. The present study suggests that EXT-DWML in nondemented elderly individuals do not necessarily indicate apparent hypoperfusion or marked cognitive decline. | White matter hyperintensities are frequent on neuroimaging of older people and are a key feature of cerebral small vessel disease. They are commonly attributed to chronic hypoperfusion, although wh... | A future lepton collider, such as the proposed CLIC or ILC, would allow to study top quark properties with unprecedented precision. In this paper, we present a method to reconstruct the $t \bar{t}$ decay in the dilepton channel at future $e^+e^-$ colliders. We derive a simple, closed analytical expression for the neutrino four-momenta as a function of the $W$ boson mass and develop a maximization procedure to find the optimal solution for the reconstruction of the full $t \bar{t}$ event. We show that our method is able to reconstruct neutrino four-momenta with an error of less than $2 \, \%$ in $60 \, \%$ of the times. Finally, we test the performance of this reconstruction method in the calculation of the helicity fractions of the $W$ boson. A precise measurement of these observables could be used to probe new physics effects in the $Wtb$ vertex. We find that, from a large $t \bar{t}$ sample, our reconstruction method allows to calculate these observables with an accuracy better than $1 \, \%$. | eng_Latn | 26,512 |
We simulate the fragmentation processes in the Ca + Ca collisions at the bombarding energy 1.05 GeV/u using the Lorentz covariant RQMD and the non covariant QMD approaches, incorporated with the statistical decay model. By comparing the results of RQMD with those of QMD, we examine the relativistic effects and find that the multiplicity of the α particle after the statistical decay process is sensitive to the relativistic effects. It is shown that the Lorentz covariant approach is necessary to analyze the fragmentation process even at the energy around E lab = 1 GeV/u as long as we are concerned with the final observables of the mass distribution, particularly, the light fragments around A = 3–4. | These lectures are based on a book “THE RELATIVISTIC NUCLEAR MANY-BODY PROBLEM” written with Brian Serot which will appear as volume 16 of the series Advances in Nuclear Physics edited by J. W. Negele and E. Vogt [R1]. I am distributing copies of the table of contents. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 26,513 |
Local models that capture the 7-brane physics of F-theory compactications for supersymmetric GUTs are conveniently described in terms of an E8 gauge theory in the presence of a Higgs bundle. Though the Higgs bundle data is usually determined by the local geometry and G-ux, additional gluing data must be specied whenever the Higgs bundle spectral cover is not smooth. In this paper, we argue that this additional information is determined by data of the M-theory 3-form that is not necessarily captured by the cohomology class of the G-ux. More specically, we show that when the 3-form is specied in terms of a line bundle on a spectral divisor, which is a global extension of the Higgs bundle spectral cover, the gluing data of the local model is uniquely determined in a way that ensures agreement with Heterotic results whenever a Heterotic dual exists. | The existence of abelian gauge symmetries in four-dimensional F-theory compactifications depends on the global geometry of the internal Calabi-Yau fourfold and has important phenomenological consequences. We study conceptual and phenomenological aspects of such U(1) symmetries along the Coulomb and the Higgs branch. As one application we examine abelian gauge factors arising after a certain global restriction of the Tate model that goes beyond a local spectral cover analysis. In SU(5) GUT models this mechanism enforces a global U(1)_X symmetry that prevents dimension-4 proton decay and allows for an identification of candidate right-handed neutrinos. We invoke a detailed account of the singularities of Calabi-Yau fourfolds and their mirror duals starting from an underlying E_8 and E_7 x U(1) enhanced Tate model. The global resolutions and deformations of these singularities can be used as the appropriate framework to analyse F-theory GUT models. | With the continuous expansion of the cloud computing platform scale and rapid growth of users and applications, how to efficiently use system resources to improve the overall performance of cloud computing has become a crucial issue. To address this issue, this paper proposes a method that uses an analytic hierarchy process group decision (AHPGD) to evaluate the load state of server nodes. Training was carried out by using a hybrid hierarchical genetic algorithm (HHGA) for optimizing a radial basis function neural network (RBFNN). The AHPGD makes the aggregative indicator of virtual machines in cloud, and become input parameters of predicted RBFNN. Also, this paper proposes a new dynamic load balancing scheduling algorithm combined with a weighted round-robin algorithm, which uses the predictive periodical load value of nodes based on AHPPGD and RBFNN optimized by HHGA, then calculates the corresponding weight values of nodes and makes constant updates. Meanwhile, it keeps the advantages and avoids the shortcomings of static weighted round-robin algorithm. | eng_Latn | 26,514 |
Considering the neutrino state like an open quantum system, we analyze its propagation in vacuum or in matter. After defining what can be called decoherence and relaxation effects, we show that in general the probabilities in vacuum and in constant matter can be written in a similar way, which is not an obvious result for such system. From this result, we analyze the situation where neutrino evolution satisfies the adiabatic limit and use this formalism to study solar neutrinos. We show that the decoherence effect may not be bounded by the solar neutrino data and review some results in the literature, in particular the current results where solar neutrinos were used to put bounds on decoherence effects through a model-dependent approach. We conclude explaining how and why these models are not general and we reinterpret these constraints. | Environmental decoherence of oscillating neutrinos of strength $\Gamma = (2.3 \pm 1.1) \times 10^{-23}$ GeV can explain how maximal $\theta_{23}$ mixing observed at 295 km by T2K appears to be non-maximal at longer baselines. As shown recently by R. Oliveira, the MSW matter effect for neutrinos is altered by decoherence: In normal (inverted) mass hierarchy, a resonant enhancement of $\nu_{\mu} (\bar{\nu}_{\mu}) \rightarrow \nu_{e} (\bar{\nu}_{e})$ occurs for $6 < E_{\nu} < 20$ GeV. Thus decoherence at the rated strength may be detectable as an excess of charged-current $\nu_{e}$ events in the full $\nu_{\mu}$ exposures of MINOS+ and OPERA. | ABSTRACTUNC-45A is an ubiquitously expressed protein highly conserved throughout evolution. Most of what we currently know about UNC-45A pertains to its role as a regulator of the actomyosin system... | eng_Latn | 26,515 |
We study the total and the geometric phase associated with neutrino mixing and we show that the phases produced by the neutrino oscillations have different values depending on the representation of the mixing matrix and on the neutrino nature. Therefore the phases represent a possible probe to distinguish between Dirac and Majorana neutrinos. | We analyze axion–photon mixing in the framework of quantum field theory. The condensate structure of the vacuum for mixed fields induces corrections to the oscillation formulae and leads to non-zero energy of the vacuum for the component of the photon mixed with the axion. This energy generates a new effect of the vacuum polarization and it has the state equation of the cosmological constant, w = − 1 . This result holds for any homogeneous and isotropic curved space–time, as well as for diagonal metrics. Numerical estimates of the corrections to the oscillation formulae are presented by considering the intensity of the magnetic field available in the laboratory. Moreover, we estimate the vacuum energy density induced by axion–photon mixing in the Minkowski space–time. A value compatible with that of the energy density of the universe can be obtained for axions with a mass of ( 10 − 3 – 10 − 2 ) eV in the presence of the strong magnetic fields that characterize astrophysical objects such as pulsars or neutron stars. In addition, a value of the energy density less than that of the Casimir effect is obtained for magnetic fields used in experiments such as PVLAS. The vacuum polarization induced by this energy could be detected in next experiments and it might provide an indirect proof of the existence of the axion–photon mixing. The quantum field theory effects presented in this work may lead to new methods for studying axion-like particles. | It is proved that special flows over irrational rotations and under functions whose Fourier coefficients are of order O(1/| n |) are disjoint in the sense of Furstenberg from all mixing flows. This is an essential strengthening of a classical result by Kocergin on the absence of mixing of special flows built over irrational rotations and under bounded variation roof functions. | eng_Latn | 26,516 |
Photosystems (PS) I and II activities depend on their lightharvesting capacity and trapping efficiency, which vary in different environmental conditions. For optimal functioning, these activities need to be balanced. This is achieved by redistribution of excitation energy between the two photosystems via the association and disassociation of light-harvesting complexes (LHC) II, in a process known as state transitions. Here we study the effect of LHCII binding to PSI on its absorption properties and trapping efficiency by comparing time-resolved fluorescence kinetics of PSI-LHCI and PSI-LHCI-LHCII complexes of Chlamydomonas reinhardtii. PSI-LHCI-LHCII of C. reinhardtii is the largest PSI supercomplex isolated so far and contains seven Lhcbs, in addition to the PSI core and the nine Lhcas that compose PSI-LHCI, together binding ∼320 chlorophylls. The average decay time for PSI-LHCI-LHCII is ∼65 ps upon 400 nm excitation (15 ps slower than PSI-LHCI) and ∼78 ps upon 475 nm excitation (27 ps slower). The transfer of excitation energy from LHCII to PSI-LHCI occurs in ∼60 ps. This relatively slow transfer, as compared with that from LHCI to the PSI core, suggests loose connectivity between LHCII and PSI-LHCI. Despite the relatively slow transfer, the overall decay time of PSI-LHCI-LHCII remains fast enough to assure a 96% trapping efficiency, which is only 1.4% lower than that of PSI-LHCI, concomitant with an increase of the absorption cross section of 47%. This indicates that, at variance with PSII, the design of PSI allows for a large increase of its light-harvesting capacities. | In this work, we have investigated the role of the individual antenna complexes and of the low-energy forms in excitation energy transfer and trapping in Photosystem I of higher plants. To this aim, a series of Photosystem I (sub)complexes with different antenna size/composition/absorption have been studied by picosecondfluorescence spectroscopy. The data show that Lhca3 and Lhca4, which harbor the most red forms, have similar emission spectra (lmax ¼ 715-720 nm) and transfer excitation energy to the core with a relative slow rate of ~25/ns. Differently, the energy transfer from Lhca1 and Lhca2, the ''blue'' antenna complexes, occurs about four times faster. In contrast to what is often assumed, it is shown that energy transfer from the Lhca1/4 and the Lhca2/3 dimer to the core occurs on a faster timescale than energy equilibration within these dimers. Furthermore, it is shown that all four monomers contribute almost equally to the transfer to the core and that the red forms slow down the overall trapping rate by about two times. Combining all the data allows the construction of a comprehensive picture of the excitation-energy transfer routes and rates in Photosystem I. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 26,517 |
A new variant of the supersymmetric fat Higgs model is presented in which the MSSM Higgses as well as the top quark are composite. The underlying theory is an s-confining SU(3) gauge theory with the MSSM gauge groups realized as gauged sub-groups of the chiral flavor symmetries. This motivates the large Yukawas necessary for the large top mass and SM-like Higgs of mass >> MZ in a natural way as the residual of the strong dynamics responsible for the composites. This removes fine-tuning associated with these couplings present in the original fat Higgs and ``new fat Higgs'' models, respectively. | We examine the possibility that the SU(2) gauge group of the standard model appears as the dual"magnetic"gauge group of a supersymmetric gauge theory, thus the W and Z (and through mixing, the photon) are composite (or partially composite) gauge bosons. Fully composite gauge bosons are expected to interact strongly at the duality scale, and a large running is needed to match the electroweak gauge couplings. Alternatively one can mix the composite"magnetic"gauge bosons with some elementary ones to obtain realistic models. In the simplest and most compelling example the Higgs and top are composite, the W and Z partially composite and the light fermions elementary. The effective theory is an NMSSM-type model where the singlet is a component of the composite meson. There is no little hierarchy problem and the Higgs mass can be as large as 400 GeV. This"fat Higgs"-like model can be considered as an explicit 4D implementation of RS-type models with gauge fields in the bulk. | A solvent-free approach for the regioselective synthesis of β-amino alcohols inshorter reaction times and higher yields, compared to conventional heating is described. Itinvolves microwave (MW) exposure of undiluted reactants in the presence of sulphatedzirconia (SZ) or sulphated zirconia over MCM-41 (SZM) as catalyst. Both acid materialscan be easily recovered and reused. | eng_Latn | 26,518 |
In the heavy-quark limit, the valence Fock-state components in the B mesons are described by a set of two light-cone wave functions. We show that these two wave functions obey simple coupled differential equations, which are based on the equations of motion in the Heavy Quark Effective Theory (HQET), and the analytic solutions for them are obtained. The results generalize the recently obtained longitudinal-momentum distribution in the Wandzura–Wilczek approximation by including the transverse momenta. We find that the transverse momentum distribution depends on the longitudinal momentum of the constituents, and that the wave functions damp very slowly for large transverse separation between quark and antiquark. | From the perspective of the hadronic physics of a decade ago it seems incredible that there now exists a viable, fundamental theory of the strong interactions. In fact, quantum chromodynamics is radically different from the picture of hadronic phenomena which was envisioned in the 1960’s. In contrast to the hadronic bootstrap, the quark and gluon quanta of QCD represent fundamental hadronic constituents, the elementary carriers of the electromagnetic and weak currents. In contrast to a strong-coupling model, the quark and gluon interactions of QCD approach scale-invariance at short distances and can be computed as a perturbative expansion in an asymptotically small coupling constant.1,2 As a consequence, the large momentum-transfer strong, electromagnetic, and weak interactions of hadrons are patterned after elementary short-distance gluon and quark subprocesses. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 26,519 |
The cold fusion phenomenon (CFP) in Solid State-Nuclear Physics (SSNP) or Condensed Matter Nuclear Science (CMNS) occurs in composite systems with regular arrangements of host nuclei (C, Ti, Ni, Pd, etc.) and intervening hydrogen isotopes (H, D). We have figured out several features of experimental data sets in the CFP showing characteristics of many-particle effects such as (1) the inverse-power law of excess power generation [1, §2.12], (2) the stability effect of transmuted product nuclei (elements) [1, §2.11], and (3) bifurcation of intensity of cold fusion (CF) effects [2]. The systems (CF materials) where occurs the CFP have common properties with those where observed complexity experimentally which has also been investigated theoretically with computer simulation. We have microscopically analyzed CF materials to find out causes of events [1, Chap. 3, 6] resulting in the above-mentioned many-particle effects and explained the occurrence of the complexity in the CFP [3]. In our analyses, it was shown that the adjustable parameter nn appeared in the TNCF model which has been successful to give several quantitative relations between numbers of reactions Nx for events X in accordance with experimental data sets seems to be useful as a parameter governing the equation describing dynamical processes resulting in complexity. Using the parameter nn as one specifying recursion relations of the cold fusion phenomenon (CFP), classical experimental data sets such as those by Fleischmann et al. (1989), De Ninno et al. (1989), and McKubre et al. (1993) have revived as typical examples showing some phases of the CFP related with complexity. Thus, the controversial questions such as reproducibility | This chapter elaborates the science of cold fusion phenomenon (CFP). The huge pile of experimental data of CFP obtained in the past 17 years is puzzling compared to the common sense of modern physics established in the last century, if this data is interpreted only from the knowledge and concepts obtained in nuclear physics and solid-state physics by the end of the 20 th century. CFP occurs in complex systems composed of solids including hydrogen isotopes and thermal neutrons, so it is fundamentally different from two-body nuclear reaction in the free space. CFP belongs to different levels of physics from those of nuclear physics and should be treated with different basic laws. This chapter discusses the TNCF model. It describes trigger reactions and breeding reactions. CFP has been explained with the TNCF model. The chapter elaborates the data by Miley. This chapter explains CEP using the TNFC model and also elaborates in detail about data by Miley. The chapter also describes CFP as a science of complexity as revealed by the stability effect and the inverse-power law. | This chapter elaborates the science of cold fusion phenomenon (CFP). The huge pile of experimental data of CFP obtained in the past 17 years is puzzling compared to the common sense of modern physics established in the last century, if this data is interpreted only from the knowledge and concepts obtained in nuclear physics and solid-state physics by the end of the 20 th century. CFP occurs in complex systems composed of solids including hydrogen isotopes and thermal neutrons, so it is fundamentally different from two-body nuclear reaction in the free space. CFP belongs to different levels of physics from those of nuclear physics and should be treated with different basic laws. This chapter discusses the TNCF model. It describes trigger reactions and breeding reactions. CFP has been explained with the TNCF model. The chapter elaborates the data by Miley. This chapter explains CEP using the TNFC model and also elaborates in detail about data by Miley. The chapter also describes CFP as a science of complexity as revealed by the stability effect and the inverse-power law. | eng_Latn | 26,520 |
Properties of the W boson in some composite models | Abstract We analyze the effects of some electroweak interaction models with a composite W at present energies. We find that the width of the W into pairs of pseudoscalar bosons can be appreciable and may reduce its leptonic branching ratio by about 20%. The front-back asymmetry of leptons at the proton-antiproton collider is similar to the one obtained in the standard model. | Abstract We present a convenient analytical parametrization, in both configuration and momentum spaces, of the deuteron wave-function calculated with the Paris potential. | eng_Latn | 26,521 |
Restrictions on the interaction between massive vector mesons | Abstract A critical investigation of the most general Lagrangian describing any number of massive vector mesons coupled through parity conserving interactions with dimensionless coupling constants is made. The theory is required to satisfy the following three conditions which are necessary on physical grounds: the presence of the interaction must not change the number of degrees of freedom of the system, the equations must describe propagation, and the propagation must take place at a speed less than that of light. One finds that some of the coupling constants are zero and others are related. The Lagrangian density takes a very simple form which generalizes, apart from the mass term, the Yang-Mills Lagrangians. | In this paper we investigate the role of the high density effects in the heavy quark production cross section in $pA$ processes at RHIC and LHC. We use, as initial condition, a gluon distribution consistent with fixed target nuclear data and the Glauber-Mueller approach to describe the high density effects. We show that this process can be used as a probe of the presence of the high density effects. Moreover, we include these effects in the calculation of the heavy quark production in $AA$ collisions, verifying that they cannot be disregarded both in the estimates of quarkonium suppression and in the initial conditions of the quark-gluon plasma. | eng_Latn | 26,522 |
A Flavor Sector for the Composite Higgs | We discuss flavor violation in large N Composite Higgs models. We focus on scenarios in which the masses of the standard model fermions are controlled by hierarchical mixing parameters, as in models of Partial Compositeness. We argue that a separation of scales between flavor and Higgs dynamics can be employed to parametrically suppress dipole and penguin operators, and thus effectively remove the experimental constraints arising from the lepton sector and the neutron EDM. The dominant source of flavor violation beyond the standard model is therefore controlled by 4-fermion operators, whose Wilson coefficients can be made compatible with data provided the Higgs dynamics approaches a"walking"regime in the IR. Models consistent with all flavor and electroweak data can be obtained with a new physics scale within the reach of the LHC. Explicit scenarios may be realized in a 5D framework, the new key ingredient being the introduction of flavor branes where the wave functions of the bulk fermions end. | Recently, both ATLAS and CMS collaborations report an excess at 750GeV in the diphoton invariant mass spectrum at 13TeV LHC. If it is a new scalar produced via loop induced gluon-gluon fusion process, it is important to know what is the particle in the loop. In this work, we investigate the possibility of determine the fraction of the contribution from the standard model top-quark in the loop. | eng_Latn | 26,523 |
Observational constraints on holographic tachyonic dark energy in interaction with dark matter | We discuss an interacting tachyonic dark energy model in the context of the holographic principle. The potential of the holographic tachyon field in interaction with dark matter is constructed. The model results are compared with CMB shift parameter, baryonic acoustic oscilations, lookback time and the Constitution supernovae sample. The coupling constant of the model is compatible with zero, but dark energy is not given by a cosmological constant. | Abstract We have designed, constructed and installed a system that makes an accurate 3D map of the electron drift velocity and measures the space-charge distorting effects in the TPCs of the DELPHI Barrel RICH detector. Details of the design considerations, construction and production are given. | eng_Latn | 26,524 |
On the spin fluctuation approach to the anderson and Kondo hamiltonians | The free energy expression of the full Anderson model is derived in a similar way as has been done before for the Kondo model. Use is made of the “asymptotic time approximation” first invented to study the x-ray threshold singularity. Again the procedure leads to a classical Coulomb gas on a ring. The magnetic field is included and plays the role of an electric field for the Coulomb gas. Further it turns out that the “symmetric” Anderson model (2e d =−U) is identical to the antiferromagnetic Kondo model. The method and the results suggest the construction of a “polaron” model which in the approximation used is equivalent to the Kondo model as well as the Anderson model. From this a new picture of the “Kondo effect” in terms of spin fluctuations is developed. | In Ref. [1] we proposed a model for Heterotic $F$-theory duality with Wilson line symmetry-breaking and a $4+1$ split of the $F$-theory spectral divisor. One goal of this note is to call attention to the existence of right-handed neutrinos in our $F$-theory model. As pointed out in Section 4 of Ref. [2] such existence may be evidence for the $U\left(1\right)_{X}$-symmetry that remains after the Higgsing of $E_{8}$ via \[ E_{8}\Rightarrow SU\left(5\right)_{gauge}\oplus\left[SU\left(4\right)\oplus U\left(1\right)_{X}\right]_{Higgs} \] occasioned by the $4+1$ split of the spectral divisor. In addition, as a result of the $\mathbb{Z}_{2}$-action that supports the Wilson line we argue that the $U\left(1\right)_{X}$-symmetry is, in fact, broken to $\mathbb{Z}_{2}$-matter parity. Finally we identify co-dimension $3$ singularities which determine Yukawa couplings for the MSSM matter fields. | eng_Latn | 26,525 |
Temperature dependence of the “0.7” 2e2/h quasi-plateau in strongly confined quantum point contacts | Abstract New results are presented of the “0.7” (2e 2 /h) quasi-plateau of strongly confined point contacts. The strong confinement is obtained by combining shallow etching with metal gate deposition on GaAs/GaAlAs heterostructures. The resulting subband separations are up to 20 meV, and consequently, the quantized conductance is observed up to 30 K, an order of magnitude higher than in conventional split gate devices. Pronounced quasi-plateaus are observed at the lowest conductance steps from 1 to 30 K, where all structures are smeared out thermally. The deviation of the conductance from ideal integer quantization exhibits an activated behavior as a function of temperature with a density-dependent activation temperature around of 2 K. Our results are analyzed in terms of a model involving scattering against plasmons in the constriction. | We study the processes $e^+ e^- \to Y(4260) \to J/\psi \pi\pi(K\bar{K})$. The strong final-state interactions, especially the coupled-channel ($\pi\pi$ and $K\bar{K}$) final-state interaction in the $S$-wave are taken into account in a model-independent way using dispersion theory. It is found that the light-quark SU(3) octet state plays a significant role in these transitions, implying that the $Y(4260)$ contains a large light-quark component. Our findings suggest that the $Y(4260)$ is neither a hybrid nor a conventional charmonium state. Furthermore, through an analysis of the ratio of the light-quark SU(3) octet and singlet components, we show that the $Y(4260)$ does not behave like a pure $\bar D D_1$ hadronic molecule as well. | eng_Latn | 26,526 |
A nuclear magnetic resonance study of SmMn2H2 | Abstract A 147 Sm and 149 Sm nuclear magnetic resonance study of the hydride SmMn 2 H 2 at 4.2 K is reported. Well resolved quadrupole septets are observed in the spectra of both isotopes. The value of the hyperfine field, 342.7 T, corresponds with the fully polarised magnetic state, J z = J =5/2, of samarium in the compound. The magnitude of the electric field gradient derived from the line separation in the spectra and the quadrupole oscillations of the spin echo decay curves reveals a considerable lattice contribution to the electric field gradient. The results are discussed in terms of the influence of hydrogen on the contribution of Sm to the magnetocrystalline anisotropy of the compound and a conclusion about the magnetic structure of the compound is given. | I discuss recent developments in the study of cosmological limits on the Minimal Supersymmetric Standard Model (MSSM). In particular, I focus on the effect of neutralino-stau coannihilation on the relic abundance of neutralinos, and I give examples where the cosmologically derived limits on the supersymmetric parameters are relaxed, and one example (CP violating phases) where they are not. | eng_Latn | 26,527 |
The 750GeV diphoton excess: who introduces it? | Recently, both ATLAS and CMS collaborations report an excess at 750GeV in the diphoton invariant mass spectrum at 13TeV LHC. If it is a new scalar produced via loop induced gluon-gluon fusion process, it is important to know what is the particle in the loop. In this work, we investigate the possibility of determine the fraction of the contribution from the standard model top-quark in the loop. | Abstract Large photovoltages proportional to length and to remanent polarizations of 40 (V/cm)/(μC/cm 2 ) have observed in wafers of ceramic BaTiO 3 + 5 wt.% CaTiO 3 . The photovoltages existed only below the Curie temperature, decreasing with increasing temperature in a linear fashion until close to the Curie temperature. | eng_Latn | 26,528 |
Quark Condensate and Nucleon-Antinucleon Phase Transition from Hadronic Models at Finite Temperature | We investigate different hadronic model parametrizations at high temperature regime. All the models were constructed to reproduce some observables at low temperature. At high temperature this study becomes important once a copious number of antiparticles arises playing an essential role in the high energy heavy-ion collision experiments like RHIC, SPS and LHC. In our study we observe a model dependent first-order phase transition at about 180 MeV. It was also verified that the order parameter, in-medium effective baryon mass, is very similar to the quark condensate as a function of the temperature. This result acquires importance since the quark condensate is the phase transition order parameter from hadronic (massive mesons) to chiral (massless mesons) phases. | We propose a simple scheme to start a parton-shower evolution description from a given jet configuration in ${e}^{+}{e}^{\ensuremath{-}}$ annihilation events. This allows a convenient combination of the full angular information content of matrix elements with the detailed sub-jet structure of parton showers, and should give a realistic overall description of event properties. Explicit studies with this hybrid approach are presented for the four-jet case, as a simple testing ground of the ideas. | eng_Latn | 26,529 |
Role of Pions and Isobars in Nuclei | Nuclear dynamics should be based on QCD with quarks and gluons interacting via a gauge field. But as we have learned during this summer school, a complete treatment of interacting quarks and gluons is hard even for a simple system like a nucleon. In order to calculate properties of a nuclear many-body system, a quark and gluon model appears prohibitively difficult. One may be able to gain some insight from non-relativistic quark models and the use of symmetry properties to relate some relevant quantities like coupling constants and masses of various particles. | Are philosophers of science limited to conducting autopsies on dead scientific theories, or might they also help resolve contemporary methodological disputes in science? This essay (1) gives an overview of thought experiments, especially in mathematics; (2) outlines three major positions on the current dose-response controversy for ionizing radiation; and (3) sketches an original mathematical thought experiment that might help resolve the low-dose radiation conflict. This thought experiment relies on the assumptions that radiation "hits'' are Poisson distributed and that background conditions cause many more radiation-induced cancers than human activities. The essay closes by responding to several key objections to the position defended here. | eng_Latn | 26,530 |
Renewables and carbon tax - a negative impact on mining and economic growth : coal & uranium | There is a concern that a rapid movement towards renewables and the introduction of a carbon tax could slow South Africa's economic growth and employment potential, without achieving the goals its proponents have put forward. | The last few years, 2013-2016, the high energy neutrino events in ICECUBE and the last rich UHECR maps by AUGER and TA were hopefully opening a new High Energy astronomy age. Unfortunately the foreseen correlation between neutrino with best gamma X sources has not (yet) been found. The most celebrated GRB gamma sources do not correlate to any neutrino events. The expected Local Group anisotropy in UHECR within the nuleon GZK cut off, has just fade away. UHECR events from Virgo are almost absent. Above two hundred TeV energy tau neutrino might shine by double bang in detectable way in ICECUBE. Within a dozen of events no tau neutrino arised (yet) in ICECUBE. Finally GRBs Fireball models calling since decades for HE neutrinos correlated imprint at TeVs energy are not (yet) found. So many absences are making a huge question mark: is there a new reading key? | eng_Latn | 26,531 |
On the determination of the leptonic decay constant fBc from QCD sum rules | Abstract The leptonic decay constant and the mass of the B c -meson are estimated using two versions of QCD sum rules. The predictions take into account the uncertainties due to the variations of the continuum threshold within the stability regions. Our optimal results are: f B c =300±65 MeV and M B c =6.25±0.20 GeV. | Several studies for the LHC luminosity upgrade pointed out the need for low-beta quadrupoles with apertures larger than the present baseline (70 mm). In this paper we focus on the design issues of a 130 mm aperture quadrupole. We first consider the Nb-Ti option, presenting a magnetic design with the LHC dipole and quadrupole cables. We study the electromagnetic forces and we discuss the field quality constraints. For the Nb3Sn option, we sketch three designs, two based on the LARP 10 mm width cable, and one on a larger cable with the same strand. The issue of the stress induced by the e.m. forces, which is critical for the Nb3Sn, is discussed using both scaling laws and finite element models. | eng_Latn | 26,532 |
Method and terminal for automatic identifying protection spacing | This invention discloses a method for automatically identifying protection intervals and terminals including: obtaining time domain pulse response of OFDM symbols based on the PN series, estimating the length of OFDM data block roughly based on the peak position of the time domain pulse response, estimating the protection interval length roughly based on the OFDM length and getting the accurate protection interval length based on the peak position in the roughly estimated protection interval, further correcting the length of the OFDM data block and determining the OFDM system transmission mode based on data block length. | We discuss some recent phenomenological models for strong interactions based on the idea of gauge/string duality. A very good estimate for hadronic masses can be found by placing an infrared cut off in AdS space. Considering static strings in this geometry one can also reproduce the phenomenological Cornell potential for a quark anti-quark potential at zero temperature. Placing static strings in an AdS Schwarzschild space with an infrared cut off one finds a transition from a confining to a deconfining phase at some critical horizon radius (associated with temperature). | eng_Latn | 26,533 |
Study of the ionized cluster beam technique | The unique aspect of Ionized Cluster Beam (ICB) thin film deposition is that material is deposited in the form of ionized, accelerated atom clusters. Unique film properties have been reported for ICB, including high surface adhesion, low temperature epitaxy, and minimal surface damage. The cluster size in much of the early work was not measured directly but was inferred from theory including the following: (1) Thermodynamic description of beam generation using a nozzle source; (2) cluster embryo formation and subsequent growth due to collisions; (3) scaling laws based on gas dynamics; (4) classical nucleation theory coupled with gas flow equations; (5) classical nucleation theory with time dependence; and (6) condensation of vapor atoms on crucible walls, surface migration to form embryos, and establishment of bonds between atoms and embryos. These theories do predict the formation of clusters using a nozzle source even though they are not in complete agreement and have their detractors. Consequently the ... | In this paper we investigate the role of the high density effects in the heavy quark production cross section in $pA$ processes at RHIC and LHC. We use, as initial condition, a gluon distribution consistent with fixed target nuclear data and the Glauber-Mueller approach to describe the high density effects. We show that this process can be used as a probe of the presence of the high density effects. Moreover, we include these effects in the calculation of the heavy quark production in $AA$ collisions, verifying that they cannot be disregarded both in the estimates of quarkonium suppression and in the initial conditions of the quark-gluon plasma. | eng_Latn | 26,534 |
Search for lepton flavour violating decays of a neutral heavy Higgs boson to $\mu\tau$ and e$\tau$ in proton-proton collisions at $\sqrt{s} =$ 13 TeV | A search for lepton flavour violating decays of a neutral non-standard-model Higgs boson in the $\mu\tau$ and e$\tau$ decay modes is presented. The search is based on proton-proton collisions at a center of mass energy $\sqrt{s} =$ 13 TeV collected with the CMS detector in 2016, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. The $\tau$ leptons are reconstructed in the leptonic and hadronic decay modes. No signal is observed in the mass range 200-900 GeV. At 95% confidence level, the observed (expected) upper limits on the production cross section multiplied by the branching fraction vary from 51.9 (57.4) fb to 1.6 (2.1) fb for the $\mu\tau$ and from 94.1 (91.6) fb to 2.3 (2.3) fb for the e$\tau$ decay modes. | Abstract We present a convenient analytical parametrization, in both configuration and momentum spaces, of the deuteron wave-function calculated with the Paris potential. | eng_Latn | 26,535 |
Titin folding energy and elasticity | Molecules of the giant protein titin are responsible for the passive elasticity and central A-band location of muscle myofibrils. The molecular mechanism of titin elasticity is not known, but the I-band region of the molecule appears capable of approximately fourfold reversible extension. Such large extensions are likely to involve unfolding of titin domains. In the present experiments, equilibrium unfolding of titin from rabbit skeletal muscles was studied in vitro by fluorescence and circular dichroism spectroscopy, after addition of guanidinium chloride. The data suggest two unfolding transitions, both of which appear cooperative. The second transition is likely to involve complete unfolding of the immunoglobulin- and fibronectin-like domains from which the molecule is composed. The free energy associated with this transition is comparable with the energy required to extend titin molecules to the maximum amount seen in situ. | The dependence of the differential cross section ${\mathrm{d}\sigma}/{\mathrm{d}p_{\perp}}$ of inclusive heavy quark production in pp and $\bar{\mathrm{p}}$p collisions on the renormalization and factorization scales is investigated. The implications of our results for experiments at TEVATRON and LHC are discussed. In particular, it is shown that the NLO QCD predictions for $\bar{t}t$ production at the LHC based on the Principle of Minimal Sensitivity are by 30-50% higher than the standard ones. | eng_Latn | 26,536 |
PROBING THE POMERON STRUCTURE WITH SPACELIKE, TIMELIKE AND REAL PHOTONS | We here propose three types of experiments in order to study the parton (gluon or quark) structure of the pomeron through electromagnetic reactions occurring at high-energy ep or colliders, where a tagging system would be used for protons (resp. antiprotons) scattered very close to 0° and with small relative energy loss. Numerical predictions are given, using models for the pomeron's structure that were recently proposed by various authors (Ingelman and Schlein, Donnachie and Landshoff). | This chapter discusses Ps.Plutarch (P), all discussing various subjects related to them. The first concerns their shape, relating to the category of quality. Ps.Galen (G) follows P rather faithfully in the chapter, except that he omits the title. Stobaeus (S) absorbs three of P's four doxai in the massive exercise of coalescence. It is easy to see that the two pairs of doxai represent two type Aetius (A) diaereses, i.e. views that are meant to be contrasted with each other. In the former the contrast involves two different kinds of shapes. In the latter the difference involves three and two dimensions. The difference between the two contrasting pairs can be neatly linked to the question raised by both Seneca and Lactantius in their set of quaestiones or ϑέσeις on the celestial realm, namely whether the stars were positioned below the outer sphere or fixed in it.Keywords: Aetius; Ps.Galen (G); Ps.Plutarch (P); Stobaeus (S) | yue_Hant | 26,537 |
Core-induced chaos in diamagnetic lithium. | We present a theoretical study of the connections between quantum and classical descriptions of lithium in a magnetic field. We find that the localized nature of the ionic core causes a breakdown in the generic connections between energy-level statistics and classical motion: classical chaos is observed in a regime where the energy-level distribution is Poissonian. The breakdown arises because the source of chaos is localized on a node of the odd-parity wave function. In addition, we employ the principles of periodic-orbit theory to identify classical trajectories with spectral periodicities. We identify a series of core-scattered recurrences in the Fourier transform of the spectrum and quantitatively describe them by a simple model. Finally, we introduce recurrence counting and demonstrate how it can help relate the classical dynamics to the quantum spectrum. \textcopyright{} 1996 The American Physical Society. | The dependence of the differential cross section ${\mathrm{d}\sigma}/{\mathrm{d}p_{\perp}}$ of inclusive heavy quark production in pp and $\bar{\mathrm{p}}$p collisions on the renormalization and factorization scales is investigated. The implications of our results for experiments at TEVATRON and LHC are discussed. In particular, it is shown that the NLO QCD predictions for $\bar{t}t$ production at the LHC based on the Principle of Minimal Sensitivity are by 30-50% higher than the standard ones. | eng_Latn | 26,538 |
Polymer dynamics: boson representation and excluded-volume forces. | The matrix formalism previously introduced for the discussion of polymer dynamics is rendered more tractable by the introduction of an explicit operator representation satisfying boson commutation rules. Techniques are devised by which singular functions of segment coordinates may be expanded in a fluctuation series (containing ordered products of boson operators) around an equilibrium or nonequilibrium average. The techniques are here applied to equilibrium excluded‐volume expansions, and are shown to give good results. The detailed numerical results are presented in the following paper. The Gaussian potential is adopted for polymer chains in a theta solvent, but methods for its improvement are considered. | The dependence of the differential cross section ${\mathrm{d}\sigma}/{\mathrm{d}p_{\perp}}$ of inclusive heavy quark production in pp and $\bar{\mathrm{p}}$p collisions on the renormalization and factorization scales is investigated. The implications of our results for experiments at TEVATRON and LHC are discussed. In particular, it is shown that the NLO QCD predictions for $\bar{t}t$ production at the LHC based on the Principle of Minimal Sensitivity are by 30-50% higher than the standard ones. | eng_Latn | 26,539 |
Singular behavior of the spectrum in the neighborhood of focus | In a recent paper [Phys. Rev. Lett.88, 013901 (2002)] it was shown that when a convergent spatially coherent polychromatic wave is diffracted at an aperture, remarkable spectral changes take place on axis in the neighborhood of certain points near the geometrical focus. In particular, it was shown that the spectrum is redshifted at some points, blueshifted at others, and split into two lines elsewhere. In the present paper we extend the analysis and show that similar changes take place in the focal plane, in the neighborhood of the dark rings of the Airy pattern. | Lattice QCD can give direct information on OZI-violating contributions to mesons. Here we explore the contributions that split flavour singlet and non-singlet meson masses. I discuss in detail the spectrum and decays for scalar mesons (ie including glueball effects). I also review the status of hybrid mesons and their decays. | eng_Latn | 26,540 |
Chiral Unitary Dynamics of Hadrons and Hadrons in a Nuclear Medium | In this talk I summarize recent findings around the description of axial vector mesons as dynamically generated states from the interaction of pseudoscalar mesons and vector mesons, dedicating some attention to the two $K_1(1270)$ states. Then I review the generation of open and hidden charm scalar and axial states, and how some recent experiment supports the existence of the new hidden charm scalar state predicted. I present recent results showing that the low lying $1/2^+$ baryon resonances for S=-1 can be obtained as bound states or resonances of two mesons and one baryon in coupled channels. Then show the differences with the S=0 case, where the $N^*(1710)$ appears also dynamically generated from the two pion one nucleon system, but the $N^*(1440)$ does not appear, indicating a more complex structure of the Roper resonance. Finally I shall show how the state X(2175), recently discovered at BABAR and BES, appears naturally as a resonance of the $\phi K \bar{K}$ system. | Abstract In this paper, we study the long-time behavior of solutions for a non-autonomous strongly damped wave equation. We first prove the existence of a uniform attractor for the equation with a translation compact driving force and then obtain an upper estimate for the Kolmogorov e -entropy of the uniform attractor. Finally we obtain an upper bound of the fractal dimension of the uniform attractor with quasiperiodic force. | eng_Latn | 26,541 |
Stability of NLO chromophores in doped polymer films during electric field poling | Thin films of organic polymers doped with specific chromophores may be used to exhibit substantial and useful second-order nonlinear optical phenomena. Such films must be subjected to DC electric field poling to eliminate the inherent inversion symmetry. In principle such poling processes may be monitored using UV absorption spectroscopy, but there are many factors which lead to ambiguity in any interpretation. In particular the authors show that the electric field poling can result in ionic-current-induced chemical transformation of the NLO chromophore to a NLO inactive moiety. They consider the stability of azo-based chromophores which are a common class of NLO chromophores. This electric field induced modification could lead to serious overestimation of any poling effects using UV spectroscopy and places limitations on potential technological applications. Such degradation does not occur in materials prepared from polymers which contain chemically linked chromophores. | We calculate the coherent charmonium photoproduction at intermediate energies accounting for the physics of the charmonium bound states and the dependence of the cross section on the region occupied by color using a correspondingly adjusted generalized vector dominance model (GVDM). In the photon energy domain where the coherence lengths are comparable to the average internucleon distances in nuclei and the nuclear radii we found that significant oscillations of the total and forward photoproduction cross sections governed by the longitudinal nuclear form factor are strongly modified by the charmonium rescatterings accounting for the nondiagonal transitions related to the color screening phenomenon. We discuss how these oscillations can influence the determination of the genuine charmonium-nucleon cross sections in the forthcoming SLAC E160 experiment on low energy J/psi and psi' photoproduction off nuclei. | eng_Latn | 26,542 |
Hard exclusive processes at HERMES | The production of mesons (or photons) in deep-inelastic lepton scattering gives access to information on the structure of hadrons that is otherwise hard to obtain. When the production process involves at least one hard scale and is exclusive, the data can be interpreted in terms of the recently introduced generalized parton distributions (GPDs). These GPDs provide a unified description of hadronic structure, which can be applied to many different reactions. It will be shown how new data collected by the HERMES experiment at DESY are used to obtain first information on GPDs. Examples of hard exclusive processes observed at HERMES include the production of pseudoscalar and vector mesons, and deeply-virtual Compton scattering. | For a large class of vanilla contingent claims, we establish an explicit F\"ollmer-Schweizer decomposition when the underlying is a process with independent increments (PII) and an exponential of a PII process. This allows to provide an efficient algorithm for solving the mean variance hedging problem. Applications to models derived from the electricity market are performed. | eng_Latn | 26,543 |
On the nature of massive phases in hypoeutegtoid CuGa alloys | Abstract Five hypoeutectoid CuGa alloys that undergo a massive transformation on cooling have been investigated by electron microscopy. It is shown that in addition to dislocations and stacking faults the massive phases contain areas of highly striated regions and that these regions may consist of a duplex structure involving f.c.c. and h.c.p. phases. The possibility that this structure is produced by growth or by a martensitic mechanism is discussed. Some details are given also of the f.c.c. structure that is produced by deformation and annealing of of the equilibrium h.c.p. phase. | Abstract In the framework of conventional Regge theory we present a common description of total photon-proton cross-section and proton structure functions in the region 0≤ Q 2 ≤5 GeV 2 . Using it as an initial condition in the perturbative QCD evolution equation, we describe structure functions at any Q 2 and x -including the small x region explored at HERA. | eng_Latn | 26,544 |
Beyond the quark model of hadrons from lattice QCD | Lattice QCD can give direct information on OZI-violating contributions to mesons. Here we explore the contributions that split flavour singlet and non-singlet meson masses. I discuss in detail the spectrum and decays for scalar mesons (ie including glueball effects). I also review the status of hybrid mesons and their decays. | We present calculations for {sup 8}Be-{sup 8}Be cluster states in {sup 16}O based on our recent schematic coupled-channels model. We justify some of the approximations made in the schematic model in this paper. The present calculations broadly support our assumptions about the states in {sup 16}O which formed the basis of our previous calculations in {sup 24}Mg. {copyright} {ital 1996 The American Physical Society.} | eng_Latn | 26,545 |
Momentum-Space Quantum Walk of Ultra-Cold Atoms | We report on a discrete-time quantum walk that uses the momentum of ultra-cold rubidium-87 atoms as the walk space and two internal atomic states as the coin degree of freedom. Each step of the walk consists of a coin toss (a microwave pulse) followed by a unitary shift operator (a resonant ratchet pulse). We review the signatures of our quantum walk and carry out a comprehensive study on the effects of various parameters, including the strength of the shift operation, coin parameters, noise, and the initialization of the system on the behavior of the walk. The walk dynamics can be well controlled in our experiment with potential applications in atom interferometry and engineering asymmetric walks. | The dependence of the differential cross section ${\mathrm{d}\sigma}/{\mathrm{d}p_{\perp}}$ of inclusive heavy quark production in pp and $\bar{\mathrm{p}}$p collisions on the renormalization and factorization scales is investigated. The implications of our results for experiments at TEVATRON and LHC are discussed. In particular, it is shown that the NLO QCD predictions for $\bar{t}t$ production at the LHC based on the Principle of Minimal Sensitivity are by 30-50% higher than the standard ones. | kor_Hang | 26,546 |
Lorentz-invariant Bohmian description of inelastic scattering in QFT | The Lorentz-invariant S-matrix elements in interacting quantum field theory (QFT) are used to represent the QFT state by a Lorentz-invariant many-time wave function. Such a wave function can be used to describe inelastic scattering processes (involving particle creation and destruction) by Bohmian particle trajectories satisfying relativistic-covariant equations of motion. | We study the processes $e^+ e^- \to Y(4260) \to J/\psi \pi\pi(K\bar{K})$. The strong final-state interactions, especially the coupled-channel ($\pi\pi$ and $K\bar{K}$) final-state interaction in the $S$-wave are taken into account in a model-independent way using dispersion theory. It is found that the light-quark SU(3) octet state plays a significant role in these transitions, implying that the $Y(4260)$ contains a large light-quark component. Our findings suggest that the $Y(4260)$ is neither a hybrid nor a conventional charmonium state. Furthermore, through an analysis of the ratio of the light-quark SU(3) octet and singlet components, we show that the $Y(4260)$ does not behave like a pure $\bar D D_1$ hadronic molecule as well. | eng_Latn | 26,547 |
Wn gravities in the light-cone gauge | Abstract A formulation of Wn gravities in the light-cone gauge is presented. A set of Ward identities in the case of W3 gravity is written down explicitly and it is indicated that it can be solved yielding correlation functions of the W-gravitons. The appearance of the SL(3, R ) current algebra is shown on the example of W3. The renormalized central charge of the analogous SL (n, R ) for the general case is calculated. The latter result is confirmed perturbatively in the limit c→∞. | In this paper we investigate the role of the high density effects in the heavy quark production cross section in $pA$ processes at RHIC and LHC. We use, as initial condition, a gluon distribution consistent with fixed target nuclear data and the Glauber-Mueller approach to describe the high density effects. We show that this process can be used as a probe of the presence of the high density effects. Moreover, we include these effects in the calculation of the heavy quark production in $AA$ collisions, verifying that they cannot be disregarded both in the estimates of quarkonium suppression and in the initial conditions of the quark-gluon plasma. | eng_Latn | 26,548 |
An “annihilation spectrometer” for investigation of heavy meson spectra | Abstract The “Rutgers Annihilation Spectrometer” (RAS) measures cross sections for antiproton annihilations as a function of the pp mass, final-state multiplicities, and degree of non-peripheralism, with a resolution of ±5 MeV and typical statistics of 10 6 events per mass bin 5 MeV wide. The non-annihilation events are suppressed by anticoinciding the events in which charged particles are emitted within the forward cones defined by the lab polar angles 2 1 2 °, 5°, 10° and 20° (4 “degrees of non-peripheralism”), eliminating single meson exchange mechanisms which are non-resonant and highly peripheral. Measurements are done at 7 incident a momenta simultaneously. Scintillation counters are the only detectors used. On-line data acquisition is accomplished by a hard-wired electronic processor (“MEGAHPOL”) capable of sorting data on 100 000 incident antiprotons per second. | We discuss some recent phenomenological models for strong interactions based on the idea of gauge/string duality. A very good estimate for hadronic masses can be found by placing an infrared cut off in AdS space. Considering static strings in this geometry one can also reproduce the phenomenological Cornell potential for a quark anti-quark potential at zero temperature. Placing static strings in an AdS Schwarzschild space with an infrared cut off one finds a transition from a confining to a deconfining phase at some critical horizon radius (associated with temperature). | eng_Latn | 26,549 |
Autistic Heterogeneity: Linking Uncertainties and Indeterminacies | AbstractAutism is a highly uncertain entity and little is said about it with any degree of certainty. Scientists must, and do, work through these uncertainties in the course of their work. Scientists explain uncertainty in autism research through discussion of epistemological uncertainties which suggest that diverse methods and techniques make results hard to reconcile, ontological uncertainties which suggest doubt over taxonomic coherence, but also through reference to autism’s indeterminacy which suggests that the condition is inherently heterogeneous. Indeed, indeterminacy takes two forms—an inter-personal form which suggests that there are fundamental differences between individuals with autism and an intra-personal form which suggests that no one factor is able to explain all features of autism within a given individual. What is apparent in the case of autism is that scientists put uncertainty and indeterminacy into discussion with one another and, rather than a well-policed epistemic-ontic boundary,... | The last few years, 2013-2016, the high energy neutrino events in ICECUBE and the last rich UHECR maps by AUGER and TA were hopefully opening a new High Energy astronomy age. Unfortunately the foreseen correlation between neutrino with best gamma X sources has not (yet) been found. The most celebrated GRB gamma sources do not correlate to any neutrino events. The expected Local Group anisotropy in UHECR within the nuleon GZK cut off, has just fade away. UHECR events from Virgo are almost absent. Above two hundred TeV energy tau neutrino might shine by double bang in detectable way in ICECUBE. Within a dozen of events no tau neutrino arised (yet) in ICECUBE. Finally GRBs Fireball models calling since decades for HE neutrinos correlated imprint at TeVs energy are not (yet) found. So many absences are making a huge question mark: is there a new reading key? | eng_Latn | 26,550 |
GAUGE HIERARCHY DUE TO STRONG INTERACTIONS | Abstract Yukawa couplings or the quartic scalar coupling may become strong at an energy scale below the unification mass. This could lead to a natural explanation of a large gauge hierarchy. The new strong interactions require the scalar mass to be larger than 173 GeV. | SummaryThe required torque leading to an abrasion of the passive layer in the stem-head interface positively correlates to the assembly force. In order to limit the risk of fretting and corrosion a... | yue_Hant | 26,551 |
The probability of pion absorption by α-clusters in nuclei | Abstract A multistep direct reaction model with pickup is extended to described the formation of tritons and 3 He-particles in nucleon- and pion-induced precompound reactions. In the latter ones, those tritons not accounted for by pickup can be explained as primary ones from absorption by α-clusters, for which a 10% probability is deduced. | The dependence of the differential cross section ${\mathrm{d}\sigma}/{\mathrm{d}p_{\perp}}$ of inclusive heavy quark production in pp and $\bar{\mathrm{p}}$p collisions on the renormalization and factorization scales is investigated. The implications of our results for experiments at TEVATRON and LHC are discussed. In particular, it is shown that the NLO QCD predictions for $\bar{t}t$ production at the LHC based on the Principle of Minimal Sensitivity are by 30-50% higher than the standard ones. | eng_Latn | 26,552 |
Evidence for 2f7/2 neutron strength in the low energy structure of 144,146,148,150Nd isotopes | Abstract The g factors of the 4 + 1 and 6 + 1 states in 144,148 Nd, the 4 + 1 state in 146 Nd and the 4 + 1 , 6 + 1 , 8 + 1 and 10 + 1 states in 150 Nd have been measured for the first time by projectile Coulomb excitation combined with the transient field technique. The g factors of the 2 + 1 states in 144,146,148,150 Nd have been remeasured with very high precision. A pronounced transition in the structure of these isotopes occurs as neutrons are removed from the rotational 150 Nd and shell closure at N =82 is approached. The g factors unambiguously reflect the increasing strength of the (2 f 7/2 ) ν n configuration. | We study the processes $e^+ e^- \to Y(4260) \to J/\psi \pi\pi(K\bar{K})$. The strong final-state interactions, especially the coupled-channel ($\pi\pi$ and $K\bar{K}$) final-state interaction in the $S$-wave are taken into account in a model-independent way using dispersion theory. It is found that the light-quark SU(3) octet state plays a significant role in these transitions, implying that the $Y(4260)$ contains a large light-quark component. Our findings suggest that the $Y(4260)$ is neither a hybrid nor a conventional charmonium state. Furthermore, through an analysis of the ratio of the light-quark SU(3) octet and singlet components, we show that the $Y(4260)$ does not behave like a pure $\bar D D_1$ hadronic molecule as well. | eng_Latn | 26,553 |
Photon Upconversion Using Baird-Type (Anti)Aromatic Quinoidal Naphthalene Derivative as a Sensitizer | A naphtho-p-quinodimethane (QDM) exhibiting Baird’s 4n – π antiaromaticity was used as green photons-harvesting chromophore to sensitize perylene (Per) leading to upconverted blue photoluminescence. The solution phase QDM → Per triplet energy transfer (TET) could not be unraveled via the Stern–Volmer method, but transient absorption measurements revealed that the kinetics of T1 → Tn for QDM (τ = 1.4 μs) was 1 order of magnitude reduced (τ = 0.17 μs) as a result of 3(Per)* formation. Furthermore, we demonstrated that incident light with power densities in the microwatt regime is sufficient to perform photon upconversion using the present set of molecular systems. | The dependence of the differential cross section ${\mathrm{d}\sigma}/{\mathrm{d}p_{\perp}}$ of inclusive heavy quark production in pp and $\bar{\mathrm{p}}$p collisions on the renormalization and factorization scales is investigated. The implications of our results for experiments at TEVATRON and LHC are discussed. In particular, it is shown that the NLO QCD predictions for $\bar{t}t$ production at the LHC based on the Principle of Minimal Sensitivity are by 30-50% higher than the standard ones. | eng_Latn | 26,554 |
Collisionless 16 μm fluorescence in SF6 following 10 μm CO2 laser pumping: Comments on the vibrational quasicontinuum | Abstract We have excited the υ 3 mode of SF 6 at 10 μm with a CO 2 laser and detected fluorescence at 16 μm from the other infrared active mode, υ 4 . The risetime of the 16 μm fluorescence is limited by the 2 μs pumping pulse width even at pressures as low as 2 mtorr, where the mean time between collisions is 60 μs. We discuss the role of the vibrational quasicontinuum in our experiment and in multiple photon infrared dissociation of SF 6 . | We present a lattice QCD calculation of the pseudoscalar decay constants $f_K$, $f_D$ and $f_{D_s}$ performed by the European Twisted Mass Collaboration with $N_f = 2 + 1 + 1$ dynamical fermions. We simulated at three different values of the lattice spacing, the smallest being approximately $0.06fm$, and with pion masses as small as $210$MeV. Our main results are: $f_{K^+}/f_{\pi^+}=1.183(17)$, $f_{K^+}=154.4(2.1)$MeV, $f_{D_s}=242.1(8.3)$MeV, $f_D=201.9(8.0)$MeV, $f_{D_s}/f_D=1.199(25)$ and $(f_{D_s}/f_D) / (f_K/f_\pi) = 1.005(15)$. | eng_Latn | 26,555 |
A comparison of biochemical and biological properties of standard and defective lymphocytic choriomeningitis virus | Abstract ::: Lymphocytic choriomeningitis (LCM) virus infection of the mouse is the best-studied model of persistent viral infection. In cell culture, persistent LCM virus infections are associated with the production of large quantities of defective interfering (DI) LCM virus. These defective interfering particles cannot replicate by themselves yet can interfere with the replication of the standard virus and prevent the cytolytic effect caused by the standard virus. It is important to determine the mechanism of interference and to establish whether the DI virus plays a role in vivo. Biological and biochemical properties of the standard and DI virus particles and also virus enzymes are compared. Antigenic analyses reveal that cells releasing only DI virus particles have less cell surface expression of viral antigens than cells releasing the standard virus. In the animal model, the DI virus is shown to have a protective effect against the pathogenesis of the LCM virus disease both in the mouse and in the rat. | We calculate the coherent charmonium photoproduction at intermediate energies accounting for the physics of the charmonium bound states and the dependence of the cross section on the region occupied by color using a correspondingly adjusted generalized vector dominance model (GVDM). In the photon energy domain where the coherence lengths are comparable to the average internucleon distances in nuclei and the nuclear radii we found that significant oscillations of the total and forward photoproduction cross sections governed by the longitudinal nuclear form factor are strongly modified by the charmonium rescatterings accounting for the nondiagonal transitions related to the color screening phenomenon. We discuss how these oscillations can influence the determination of the genuine charmonium-nucleon cross sections in the forthcoming SLAC E160 experiment on low energy J/psi and psi' photoproduction off nuclei. | eng_Latn | 26,556 |
Knockout by John Jodzio (review) | <p>A review of <i>Knockout</i> by John Jodzio, reviewed by Steffan Hruby.</p> | Abstract At an interface or junction, strong spin-orbit coupling with pairing inhomogeneity and small pair size on the heavy-electron side mean that coherent proximity or Josephson effects would occur for singlet to triplet as well as for singlet to singlet pairing states. | eng_Latn | 26,557 |
Quantum Transition from Order to Chaos in the Nuclear Shell Model 1 | We discuss the role of quantum chaos in atomic nuclei. After reviewing the basic assumptions of the nuclear shell model, we analyze the spectral statistics of the energy levels obtained with realistic shell-model calculations in the fp shell. In particular, for Ca isotopes we observe a transition from order to chaos by increasing the excitation energy and a clear quantum signature of the breaking of integrability by changing the single-particle spacings. | Uncertainties in neutrino interaction cross-sections affect modern long-baseline neutrino oscillation experiments like NOvA. Detailed within is how NOvA handles these uncertainties, especially for 2p2h interactions, how the effects of these cross-section uncertainties are quantified, and how NOvA’s cross-section simulation is tuned to better match data. | eng_Latn | 26,558 |
The Casimir-Polder interaction between two neutrons and possible relevance to tetraneutron states | We present a summary of our recent publication concerning the derivation of the extended Casimir-Polder dispersive interaction between two neutrons. Dynamical polarizations of the neutrons, recently derived within Chiral Effective Theory are used for the purpose. An account of the higher frequency/energy behavior of these entities related to the opening of one-pion production channel and the excitation of the $\Delta$ resonance are taken into consideration in our derivation of the CP interaction. The neutron-neutron system in free space is treated in details so are the neutron-wall and the wall-neutron-wall systems. The case of tetraneutron (a 4 neutron system) in a resonant state is then briefly considered. The 4n CP interaction is evaluated to assess its potential relevance to the ongoing debate concerning the nature of the tetraneutron. | Cationic fluorophore homodimer probes 1 and 2 bearing 7-aminocoumarin and naphthalimide dyes, respectively, connected via diethylenetriamine (DETA) spacer, have been developed to demonstrate the validity of our modular probe design on the basis of the triamine-based spacer. | eng_Latn | 26,559 |
Born—Oppenheimer Separation for Three‐Particle Systems. I. Theory | The Born—Oppenheimer separation for a three‐particle system has been re‐examined in detail using a variational approach including a scale parameter. Discrepancies arising in earlier work have been resolved. Tables of adiabatic and nonadiabatic coupling terms are presented. | Measurements performed at the Tevatron of both the like-sign dimuon charge asymmetry inBd;s-meson samples and the mixing-induced CP asymmetry inBs! J= depart from their standard model (SM) predictions. This could be an indication for new CP phases in B = 2 transitions, preferentially in Bs{ Bs mixing. The experimental situation, however, remained inconclusive, as it favored values of the element s of the decay matrix in the Bs-meson system that are notably dierent | kor_Hang | 26,560 |
Torsion Gravity for Dirac Particles | In this paper we consider torsion gravity in the case of the Dirac field, and by going into the rest frame we study what happens when a uniform precession as well as a phase are taken into account for the spinor field; we discuss how partially conserved axial-vector currents and torsion-spin attractive potentials justify negative Takabayashi angle and energy smaller than mass: because in this instance the module goes to zero exponentially fast then we obtain stable and localized matter distributions suitable to be regarded as a description of particles. | We study the effects of gluon radiation on top production and decay processes at an $e^+e^-$ collider.The matrix elements are computed without any approximations, using spinor techniques. We use a Monte Carlo event generator which takes into account the infrared singularity due to soft gluons and differences in kinematics associated with radiation in the production versus decay process. The calculation is illustrated for several strategies of top mass reconstruction. | eng_Latn | 26,561 |
Semileptonicbctoccbaryon decay and heavy quark spin symmetry | We study the semileptonic decays of the lowest-lying bc baryons to the lowest-lying cc baryons ::: (b0c ! cc and 0 bc ! cc), in the limit mb;mc QCD and close to the zero-recoil point. The ::: separate heavy quark spin symmetries make it possible to describe all these decays using a single form ::: factor. We recover results derived previously by White and Savage in a manner which we think is more ::: straightforward and parallels the method applied later to study Bc semileptonic decays. We further discuss ::: the resemblance between the bc baryon decays and those of Bc mesons to c and J= mesons and ::: comment on the relation between the slopes of the single functions describing each set of decays. Our ::: results can straightforwardly be applied to the decays of bb baryons to bc baryons. | The 3s,3p satellite spectrum of argon has been studied with use of synchrotron radiation in the 40--70-eV energy range. In the region of the 3s Cooper minimum (42.5 eV\ifmmode\pm\else\textpm\fi{}0.2), the integral intensity of the satellites is ten times larger than the 3s partial cross section. The angular asymmetry parameters have been measured as a function of the photoelectron energy for the 3s ${}^{2}$S,3p ${}^{2}$P final states as well as for the satellites. For the lowest photon energies it appears that the \ensuremath{\beta} parameter values of the most intense satellites are strongly dependent on the total angular momentum of the final ionic state. | eng_Latn | 26,562 |
Mechanism of the Lewis acid mediated cleavage of chiral acetals | The TiCl 4 -promoted cleavage of acetals has been shown to proceed by different mechanisms depending on the structure of the acetal, making it difficult to draw firm conclusions about the mechanism of related acetals based on model studies | We study how the elements of the leptonic right-handed mixing matrix can be determined at the LHC in the minimal Left-Right symmetric extension of the standard model. We do it by explicitly relating them with physical quantities of the Keung-Senjanovi\'c process and the lepton number violating decays of the right doubly charged scalar. We also point out that the left and right doubly charged scalars can be distinguished at the LHC, without measuring the polarization of the final state leptons coming from their decays. | eng_Latn | 26,563 |
Neutralization process of depolarization field in L-α-alanine doped triglycine sulfate | Abstract The neutralization process of the depolarization field in L-α-alanine doped triglycine sulfate (LATGS) was investigated by the observation of the polarization charge on the surface of LATGS from the moment of cleavage. The charges which were equivalent to such a high voltage as 5kV were actually induced on the surface of the sample at the moment when the sample was cleaved. The charges were neutralized exponentially with time and more slowly in the vacuum cell (≊10Pa) than in atmosphere. | The $\Lambda\Lambda$-$\Xi N$-$\Sigma\Sigma$ coupling in $^{~6}_{\Lambda\Lambda}$He is studied with the [$\alpha$ + $\Lambda$ + $\Lambda$] + [$\alpha$ + $\Xi$ + $N$] + [$\alpha$ + $\Sigma$ + $\Sigma$] model, where the $\alpha$ particle is assumed as a frozen core. We use the Nijmegen soft-core potentials, NSC97e and NSC97f, for the valence baryon-baryon part, and the phenomenological potentials for the $\alpha-B$ parts ($B$=$N$, $\Lambda$, $\Xi$ and $\Sigma$). We find that the calculated $\Delta B_{\Lambda\Lambda}$ of $^{~6}_{\Lambda\Lambda}$He for NSC97e and NSC97f are, respectively, 0.6 and 0.4 MeV in the full coupled-channel calculation, the results of which are about half in comparison with the experimental data, $\Delta B^{exp}_{\Lambda\Lambda}=1.01\pm0.20^{+0.18}_{-0.11}$ MeV. Characteristics of the $S=-2$ sector in the NSC97 potentials are discussed in detail. | eng_Latn | 26,564 |
The demonstration on wave front in the uniaxial crystal | A new small sized demonstration apparatus is introduced.It can be used to demonstrate such as optical axis of the uniaxial crystal,principal plane,the ordinary wave front and the extraordinary wave front,etc.,and to explain what situation will give rise to the phenomenon of double refraction for the various examples of curriculum. | In Ref. [1] we proposed a model for Heterotic $F$-theory duality with Wilson line symmetry-breaking and a $4+1$ split of the $F$-theory spectral divisor. One goal of this note is to call attention to the existence of right-handed neutrinos in our $F$-theory model. As pointed out in Section 4 of Ref. [2] such existence may be evidence for the $U\left(1\right)_{X}$-symmetry that remains after the Higgsing of $E_{8}$ via \[ E_{8}\Rightarrow SU\left(5\right)_{gauge}\oplus\left[SU\left(4\right)\oplus U\left(1\right)_{X}\right]_{Higgs} \] occasioned by the $4+1$ split of the spectral divisor. In addition, as a result of the $\mathbb{Z}_{2}$-action that supports the Wilson line we argue that the $U\left(1\right)_{X}$-symmetry is, in fact, broken to $\mathbb{Z}_{2}$-matter parity. Finally we identify co-dimension $3$ singularities which determine Yukawa couplings for the MSSM matter fields. | eng_Latn | 26,565 |
Low ion velocity slowing down in a strongly magnetized plasma target | Abstract Ion projectile stopping at velocity smaller than target electron thermal velocity in a strong magnetic field, is investigated within a novel diffusion formulation (Dufty–Berkovsky), based on Green–Kubo integrands evaluated in magnetized one component plasma models, respectively framed on target ions and electrons. Analytic expressions are reported for slowing down orthogonal and parallel to an arbitrary large magnetic field, which are free from the usual uncertainties plaguing the standard perturbative derivations. | We discuss flavor violation in large N Composite Higgs models. We focus on scenarios in which the masses of the standard model fermions are controlled by hierarchical mixing parameters, as in models of Partial Compositeness. We argue that a separation of scales between flavor and Higgs dynamics can be employed to parametrically suppress dipole and penguin operators, and thus effectively remove the experimental constraints arising from the lepton sector and the neutron EDM. The dominant source of flavor violation beyond the standard model is therefore controlled by 4-fermion operators, whose Wilson coefficients can be made compatible with data provided the Higgs dynamics approaches a"walking"regime in the IR. Models consistent with all flavor and electroweak data can be obtained with a new physics scale within the reach of the LHC. Explicit scenarios may be realized in a 5D framework, the new key ingredient being the introduction of flavor branes where the wave functions of the bulk fermions end. | eng_Latn | 26,566 |
SPACE AND CHARGE PARITY OF A PROTON-ANTIPROTON SYSTEM AND ITS TWO-MESON ANNIHILATION | If a proton and antiproton are described by the Dirac equation the (p,p) system will possess a definite charge and space parity. To check this consequence of the Dirac equation it is suggested that p + p -- pi /sup +/ + pi - and -p + p -pi + pi /sup 0/ annihilation experiments be performed. (auth) | Abstract We present a convenient analytical parametrization, in both configuration and momentum spaces, of the deuteron wave-function calculated with the Paris potential. | yue_Hant | 26,567 |
Experimental evidence for a light and broad scalar resonance in $D^+\to \pi^-\pi^+\pi^+$ decay | From a sample of $1172 \pm 61$ $D^+ \to \pi^- \pi^+ \pi^+$ decay, we find $\Gamma (D^+ \to \pi^- \pi^+ \pi^+) / \Gamma (D^+ \to K^- \pi^+ \pi^+) = 0.0311 \pm 0.0018 ^{+0.0016}_{-0.0026}$. Using a coherent amplitude analysis to fit the Dalitz plot of this decays, we find strong evidence that a scalar resonance of mass $478^{+24}_{-23} \pm 17$ MeV/$c^2$ and width $324^{+42}_{-40} \pm 21$ MeV/$c^2$ accounts for approximately half of all decays. | This paper discusses the dynamical properties of p-spin models with Kac interactions. For large but finite interaction range R one finds two different well separated time scales for relaxation. A first short time scale, roughly independent of R, on which the system remains confined to limited regions of the configuration space and an R dependent long time scale on which the system is able to escape from the confining regions. I will argue that the R independent time scales can be described through dynamical mean field theory, while non-perturbative new techniques have to be used to deal with the R dependent scales. | eng_Latn | 26,568 |
Ghost free analysis of a nonsymmetric theory of gravitation | The absence of ghost-negative energy radiative modes in a proposed generalized theory of gravitation based on a non-symmetric metric is reanalyzed. The missing contribution of the symmetric sector of the Lagrangian is calculated and shown to be null. The ghost free character of the theory is then firmly established. | Measurements performed at the Tevatron of both the like-sign dimuon charge asymmetry inBd;s-meson samples and the mixing-induced CP asymmetry inBs! J= depart from their standard model (SM) predictions. This could be an indication for new CP phases in B = 2 transitions, preferentially in Bs{ Bs mixing. The experimental situation, however, remained inconclusive, as it favored values of the element s of the decay matrix in the Bs-meson system that are notably dierent | eng_Latn | 26,569 |
On the two-loop contributions to the pion mass | We derive a simplified representation for the pion mass to two loops in three-flavour chiral perturbation theory. For this purpose, we first determine the reduced expressions for the tensorial two-loop 2-point sunset integrals arising in chiral perturbation theory calculations. Making use of those relations, we obtain the expression for the pion mass in terms of the minimal set of master integrals. On the basis of known results for these, we arrive at an explicit analytic representation, up to the contribution from KKη intermediate states where a closed-form expression for the corresponding sunset integral is missing. However, the expansion of this function for a small pion mass leads to a simple representation which yields a very accurate approximation of this contribution. Finally, we also give a discussion of the numerical implications of our results. | Measurements performed at the Tevatron of both the like-sign dimuon charge asymmetry inBd;s-meson samples and the mixing-induced CP asymmetry inBs! J= depart from their standard model (SM) predictions. This could be an indication for new CP phases in B = 2 transitions, preferentially in Bs{ Bs mixing. The experimental situation, however, remained inconclusive, as it favored values of the element s of the decay matrix in the Bs-meson system that are notably dierent | eng_Latn | 26,570 |
BEC of Two Photons and Higgs Physics | It is well understood that the studies of correlations between produced particles, the effects of coherence and chaoticity, an estimation of particle emitting source size play an important role in high energy physics [1]. We mean the investigation of the space-time extension or even squeezing of particle sources via the multiparticle quantum-statistics correlation. We obtain the two-photon correlation function that can provide the space-time information about the Higgs-boson source in thermal environment and we argue that such an investigation could probe the Higgs-boson mass. | Abstract In this paper, we analyze photometry of V504 Cyg semi-detached binary system. For this purpose, after taking the photometric data, primary and secondary minimum and new epoch were calculated. The period of system is found to be 0.3516916 day. Analysis of light curve was performed by PHOEBE software which uses last version of Wilson–Devinney code. 3D model of the system is worked out using Binary Maker software. The O’Connell effect in the light curve is observed and an accurate model of this system is presented by introducing four spots on the components. | yue_Hant | 26,571 |
Introduction to High Energy Physics | 1. Introduction and Overview. 2. Particle Detectors and Accelerators. 3. Invariance Principles and Conservation Laws. 4. Hadron-Hadron Interactions. 5. Static Quark Model of Hadrons. 6. Electromagnetic Interactions. 7. Weak Interactions. 8. Quark-Quark Interactions: The Parton Model and QCD. 9. The Unification of Electroweak and Other Interactions. Appendices. Tables. Solutions to Problems. References. Index. | In this paper we study a degenerate evolution system ::: $\mathbf H_t +\nabla \times [|\nabla \times \mathbf H|^{p-2}\nabla \times \mathbf H]=\mathbf F$ in a bounded domain as well as its limit as $p\to \infty$ subject ::: to appropriate initial and boundary conditions. This system governs the evolution ::: of the magnetic field $\mathbf H$ in a conductive medium under the influence of a system ::: force $\mathbf F$. The system is an approximation of Bean's critical-state model for type-II superconductors. The existence, uniqueness and regularity of solutions to the ::: system are established. Moreover, it is shown that the limit of $\mathbf H(x, t)$ as $p\to \infty$ ::: is a solution to the Bean model. | kor_Hang | 26,572 |
Closing a quantum feedback loop inside a cryostat: Autonomous state preparation and long-time memory of a superconducting qubit | We propose to use a cryogenic nonlinear resonator for the projective readout, classical memory, and feedback for a superconducting qubit. This approach sidesteps many of the inefficiencies inherent in two-way communication between temperature stages in typical systems with room temperature controllers, and avoids increasing the cryogenic heat load. This controller may find a broad range of uses in multi-qubit systems, but here we analyze two specific demonstrative cases in single qubit-control. In the first case, the nonlinear controller is used to initialize the qubit in a definite eigenstate. And in the second case, the qubit's state is read into the controller's classical memory, where it is stored for an indefinite period of time, and then used to reinstate the measured state after the qubit has decayed. We analyze the properties of this system and we show simulations of the time evolution for the full system dynamics. | We discuss some recent phenomenological models for strong interactions based on the idea of gauge/string duality. A very good estimate for hadronic masses can be found by placing an infrared cut off in AdS space. Considering static strings in this geometry one can also reproduce the phenomenological Cornell potential for a quark anti-quark potential at zero temperature. Placing static strings in an AdS Schwarzschild space with an infrared cut off one finds a transition from a confining to a deconfining phase at some critical horizon radius (associated with temperature). | eng_Latn | 26,573 |
XENON: A 1 TONNE LIQUID XENON EXPERIMENT FOR A SENSITIVE DARK MATTER SEARCH | XENON is a novel liquid xenon experiment concept for a sensitive dark matter search using a 1-tonne active target, distributed in an array of ten independent time projection chambers. The design relies on the simultaneous detection of ionization and scintillation signals in liquid xenon, with the goal of extracting as much information as possible on an event-by-event basis, while maintaining most of the target active. XENON is expected to have effective and redundant background identification and discrimination power, higher than 99.5%, and to achieve a very low threshold, on the order of 4 keV visible recoil energy. ::: Based on this expectation and the 1-tonne mass of active xenon, we project a sensitivity of 0.0001 events/kg/day, after 3 yr operation in an appropriate underground location. The XENON experiment has been recently proposed to the National Science Foundation (NSF) for an initial development phase leading to the development of the 100 kg unit module. | In this paper we investigate the role of the high density effects in the heavy quark production cross section in $pA$ processes at RHIC and LHC. We use, as initial condition, a gluon distribution consistent with fixed target nuclear data and the Glauber-Mueller approach to describe the high density effects. We show that this process can be used as a probe of the presence of the high density effects. Moreover, we include these effects in the calculation of the heavy quark production in $AA$ collisions, verifying that they cannot be disregarded both in the estimates of quarkonium suppression and in the initial conditions of the quark-gluon plasma. | yue_Hant | 26,574 |
Determination of BR(chi_{cJ} --> p \bar{p}) in psi(2S) decays | The processes psi(2S) --> gamma chi_{cJ}, chi_{cJ} --> p pbar (J=0,1,2) are studied using a sample of 14X10^6 psi(2S) decays collected with the Beijing Spectrometer at the Beijing Electron-Positron Collider. Very clear chi_{c0}, chi_{c1} and chi_{c2} signals are observed, and the branching fractions BR(chi_{cJ} --> p pbar) (J=0,1,2) are determined to be (27.1^{+4.3}_{-3.9}\pm 4.7)X10^{-5}, ::: (5.7^{+1.7}_{-1.5}\pm0.9)X10^{-5}, and (6.5^{+2.4}_{-2.1}\pm1.0)X10^{-5}, respectively, where the first errors are statistical and the second are systematic. | 4 pages.-- PACS numbers: 05.45.Xt, 87.10.+e.-- ArXiv pre-print: http://arxiv.org/abs/nlin.CD/0512009.-- Final full-text version of the paper available at: http://dx.doi.org/10.1103/PhysRevE.73.055202. | eng_Latn | 26,575 |
An Intuitive Approach to the Coherent and Squeezed States of the Quantum Harmonic Oscillator | The purpose of this work is to introduce, in a simple, intuitive way, the coherent and squeezed states of the quantum harmonic oscillator (QHO), through a series of exercises, which are solved in detail. Starting from the application of a spatial translation to the ground state of the QHO, we introduce the spatial and momentum translations, focusing on their application to the QHO, which leads us to the displacement operator. Next, we introduce the coherent states and examine their basic aspects. We then proceed to give a simple and purely intuitive introduction to the squeezed states and we conclude by identifying the coherent states as states of minimum energy expectation value compared to the respective squeezed states. The reader is assumed to have a basic knowledge of the postulates and the mathematical formalism of quantum mechanics, including the Dirac notation and the ladder operator method of the QHO. | Lattice QCD can give direct information on OZI-violating contributions to mesons. Here we explore the contributions that split flavour singlet and non-singlet meson masses. I discuss in detail the spectrum and decays for scalar mesons (ie including glueball effects). I also review the status of hybrid mesons and their decays. | eng_Latn | 26,576 |
Synthesis and luminescence of ceria decorated graphene quantum dots (GQDs): Evolution of band gap | ABSTRACT Graphene quantum dots (GQDs) and CeO2-GQDs were synthesized by using a facile hydrothermal method at 140°C. All the synthesized materials were characterized by TEM, UV-Vis Spectroscopy, FT-IR, Raman Spectroscopy and PL. Ceria decorated GQDs show different emission peaks with different excitation of wavelengths. The discrete change in dominant luminescence features of the GQDs and their composites indicate that the variation in PL occurs because of alteration in its shape, size and bandgap. Based on the experimental results of PL peak wavelength, the emission is attributed to quasi-molecular PL from the fragments composed of a few aromatic rings with oxygen containing functional groups. | We study the processes $e^+ e^- \to Y(4260) \to J/\psi \pi\pi(K\bar{K})$. The strong final-state interactions, especially the coupled-channel ($\pi\pi$ and $K\bar{K}$) final-state interaction in the $S$-wave are taken into account in a model-independent way using dispersion theory. It is found that the light-quark SU(3) octet state plays a significant role in these transitions, implying that the $Y(4260)$ contains a large light-quark component. Our findings suggest that the $Y(4260)$ is neither a hybrid nor a conventional charmonium state. Furthermore, through an analysis of the ratio of the light-quark SU(3) octet and singlet components, we show that the $Y(4260)$ does not behave like a pure $\bar D D_1$ hadronic molecule as well. | eng_Latn | 26,577 |
Higher order QCD corrections to the photoproduction of a direct photon at HERA | The contribution of resolved photons to the photoproduction cross section of direct photons is reexamined. Higher order,O(α2αs), QCD corrections to this contribution are calculated and turn out to be important at HERA energies. The observation of direct photons in the medium-p⊥ range (p⊥∼5 GeV/c) should provide the opportunity to measure the gluon content of the photon. | We investigate the rearrangement of the Haar system induced by the postorder on the set of dyadic intervals in $[0,1]$ with length greater than or equal to $2^{-N}$. By means of operator norms on $\text{BMO}_N$ we prove that the postorder has maximal distance to the usual lexicographic order. | eng_Latn | 26,578 |
A note on the interpretation ofE 1,E 1+Δ 1 transitions in Ge | The paper deals with problems of the interpretation ofE1,E1+Δ1 transitions near 2 eV in Ge. The treatment of ac piezoreflectance spectra of Ge in this energy region shows that the transitionse1,E1+Δ1 are, in general, not well-described by any model of the pair of parabolic critical points of the same type; therefore neither of both frequently used models (3DM1-pair or 2DM0- pair) is appropriate. The hydrostatic componentW1(E) of the piezooptic tensor was extracted from the experimental ac piezoreflectance spectra and then treated by the symmetrization method for the precise determination of transition energies. This method does not depend on the type of the critical points pair and it is based on the existence of a symmetric linear combination of real and imaginary parts of the critical point contribution to the dielectric function. | Recently Davoudiasl {\it et al} \cite{steinhardt} have introduced a new type of interaction between the Ricci scalar $R$ and the baryon current $J^{\mu}$, ${\partial_\mu R} J^{\mu}$ and proposed a mechanism for baryogenesis, the gravitational baryogenesis. Generally, however, $\partial_{\mu} R$ vanishes in the radiation dominated era. In this paper we consider a generalized form of their interaction, $\partial_{\mu}f(R)J^{\mu}$ and study again the possibility of gravitational baryo(lepto)genesis. Taking $f(R)\sim \ln R$, we will show that $\partial_{\mu}f(R)\sim \partial_{\mu} R/R$ does not vanish and the required baryon number asymmetry can be {\it naturally} generated in the early universe. | eng_Latn | 26,579 |
SEARCHES FOR NEW PHYSICS AT HERA | Recent results from searches for new physics at HERA are reviewed. Exploiting the uniqueness of lepton-hadron collisions at high energy, searches are performed for electron-quark resonant states (leptoquarks or squarks in R-parity-violating supersymmetry) or excited states of fermions. New phenomena at a very high energy scale, manifested at present energies as effective four-fermion contact interaction, are also investigated, including cases with lepton-flavor violation. Finally, the status of events with a high-energy lepton and missing transverse momentum is presented, resulting in the most stringent constraint on the flavor-changing neutral current t-u-\gamma coupling which could yield single-top production. | Abstract The structures observed in recent missing mass experiments 3 He(p, d)X and p( 3 He, d)X are discussed and shown to agree to a high accuracy with a rotational like scheme M = M 0 + M 1 J ( J +1). An explanation is suggested as to why these structures have not been observed in some other experiments. | yue_Hant | 26,580 |
Reply to Reviews by Slavin, Stein, and Stern | This paper elaborates on Ken Corbett's sense of inclusive and paradoxical solutions to what are traditionally described as conflicts of gender. | Inspired by the newly observed two charged bottomonium-like states, we consider the possible contribution from the intermediate $Z_b(10610)$ and $Z_b(10650)$ states to the $\Upsilon(5S)\to \Upsilon(2S)\pi^+\pi^-$ decay process, which naturally explains Belle's previous observation of the anomalous $\Upsilon(2S)\pi^+\pi^-$ production near the peak of $\Upsilon(5S)$ at $\sqrt s=10.87$ GeV [K.F. Chen {\it et al}. (Belle Collaboration), Phys. Rev. Lett. {\bf 100}, 112001 (2008)]. The resulting $d\Gamma(\Upsilon(5S)\to \Upsilon(2S)\pi^+\pi^-)/dm_{\pi^+\pi^-}$ and $d\Gamma(\Upsilon(5S)\to \Upsilon(2S)\pi^+\pi^-)/d\cos\theta$ distributions agree with Belle's measurement after inclusion of these $Z_b$ states. This formalism also reproduces the Belle observation of the double-peak structure and its reflection in $\Upsilon(2S)\pi^+$ invariant mass spectrum of $\Upsilon(5S)\to \Upsilon(2S)\pi^+\pi^-$ decay. | eng_Latn | 26,581 |
The impacts of the quantum-dot confining potential on the spin-orbit effect | For a nanowire quantum dot with the confining potential modeled by both the infinite and the finite square wells, we obtain exactly the energy spectrum and the wave functions in the strong spin-orbit coupling regime. We find that regardless of how small the well height is, there are at least two bound states in the finite square well: one has the σx$${\mathscr{P}}$$P = −1 symmetry and the other has the σx$${\mathscr{P}}$$P = 1 symmetry. When the well height is slowly tuned from large to small, the position of the maximal probability density of the first excited state moves from the center to x ≠ 0, while the position of the maximal probability density of the ground state is always at the center. A strong enhancement of the spin-orbit effect is demonstrated by tuning the well height. In particular, there exists a critical height $${V}_{0}^{c}$$V0c, at which the spin-orbit effect is enhanced to maximal. | Abstract Exotic pentaquark baryon with strangeness +1, Θ+, is studied in the QCD sum rule approach. We derive sum rules for the positive and negative parity baryon states with J= 1 2 and I=0. It is found that the standard values of the QCD condensates predict a negative parity Θ+ of mass ≃1.5 GeV, while no positive parity state is found. We stress the roles of chiral-odd condensates in determining the parity and mass of Θ+. | eng_Latn | 26,582 |
A Supersymmetric Explanation of the Excess of Higgs--Like Events at the LHC and at LEP | The LHC collaborations have recently announced evidence for the production of a "Higgs--like" boson with mass near 125 GeV. The properties of the new particle are consistent (within still quite large uncertainties) with those of the Higgs boson predicted in the Standard Model (SM). This discovery comes nearly ten years after a combined analysis of the four LEP experiments showed a mild excess of Higgs--like events with a mass near 98 GeV. I show that both groups of events can be explained simultaneously in the minimal supersymmetric extension of the SM, in terms of the production and decay of the two neutral CP--even Higgs bosons predicted by this model, and explore the phenomenological consequences of this explanation. | The Hodges-Lehmann estimator was originally developed as a non-parametric estimator of a shift parameter. As it is widely used in statistical applications, the question is investigated what it is estimating if the shift model does not hold. It is shown that for data whose distributions are symmetric about their median the Hodges–Lehmann estimator based on the Wilcoxon Rank Sum test estimates the difference between the medians of the distributions. This result does generally not hold if the symmetry assumption is violated. Copyright © 2009 John Wiley & Sons, Ltd. | eng_Latn | 26,583 |
A calibration of the sub-coulomb (t, d) reaction | Abstract An activation technique has been used in measurements of the absolute thick target yield of the 48 Ca(t, d) 49 Ca(g.s.) reaction at triton energies below the Coulomb barrier at 2.50, 2.75, 3.00, 3.25 and 3.50 MeV. Prom a DWBA analysis of the data the value of the sub-Coulomb (t, d) normalisation factor D 2 has been determined to be (3.47 ±0.42) × 10 4 MeV 2 · fm 3 . The calibration relies on a comparison of data from the 48 Ca(t, d) 49 Ca(g.s.) reaction with that from the sub-Coulomb 48 Ca( 17 O, 16 O) 49 Ca(g.s.) reaction. The sensitivity of the results to the available optical-model parameter sets is discussed. | The $\Lambda\Lambda$-$\Xi N$-$\Sigma\Sigma$ coupling in $^{~6}_{\Lambda\Lambda}$He is studied with the [$\alpha$ + $\Lambda$ + $\Lambda$] + [$\alpha$ + $\Xi$ + $N$] + [$\alpha$ + $\Sigma$ + $\Sigma$] model, where the $\alpha$ particle is assumed as a frozen core. We use the Nijmegen soft-core potentials, NSC97e and NSC97f, for the valence baryon-baryon part, and the phenomenological potentials for the $\alpha-B$ parts ($B$=$N$, $\Lambda$, $\Xi$ and $\Sigma$). We find that the calculated $\Delta B_{\Lambda\Lambda}$ of $^{~6}_{\Lambda\Lambda}$He for NSC97e and NSC97f are, respectively, 0.6 and 0.4 MeV in the full coupled-channel calculation, the results of which are about half in comparison with the experimental data, $\Delta B^{exp}_{\Lambda\Lambda}=1.01\pm0.20^{+0.18}_{-0.11}$ MeV. Characteristics of the $S=-2$ sector in the NSC97 potentials are discussed in detail. | eng_Latn | 26,584 |
Quantum effects in beam-plasma instabilities | Among the numerous works on quantum effects that have been published in recent years, streaming instabilities in plasma have also been revisited. Both the fluid quantum and the kinetic Wigner-Maxwell models have been used to explore quantum effects on the Weibel, Filamentation and Two-Stream instabilities. While quantum effects usually tend to reduce the instabilities, they can also spur new unstable branches. A number of theoretical results will be reviewed together with the implications to one physical setting, namely the electron driven fast ignition scenario. | Abstract Within the framework of perturbative QCD I show that the high energy factorization formula for jets observables resumming to all orders the leading log(s) can be extended to next-to-leading log(s) approximation. In addition, I provide the last missing factor of such a formula, namely the NL correction to the jet-production vertex. This makes it possible to perform accurate analyses of high energy processes like dijets at hadron-hadron colliders as well as forward jets at lepton-hadron colliders in a framework that is now consistent with both DGLAP evolution and BFKL evolution, providing a quantitative tool for exploring QCD in the high energy regime. | eng_Latn | 26,585 |
Corona Discharge Simulation of Multiconductor Electrostatic Precipitators | This paper considers corona discharge problems with multiple conductors, such as those appearing in some electrostatic precipitators. A common precise condition is identified in which the previous approaches proposed in the literature fail. For dealing with these conditions, a novel, stabilized, and regularized formulation of the problem is proposed. Moreover, a Newton–Raphson scheme is defined for iteratively solving a nonstandard Petrov–Galerkin finite-element discretization of the problem. The presented approach is validated on a benchmark for which an analytical solution is known and its applicability to problems of industrial relevance is shown. | We analyze the interplay of topological objects in four dimensional QCD. The distributions of color magnetic monopoles obtained in the maximum abelian gauge are computed around instantons in both pure and full QCD. We find an enhanced probability of encountering monopoles inside the core of an instanton on gauge field average. For specific gauge field configurations we visualize the situation graphically. Moreover we investigate how monopole loops and instantons are locally correlated with the chiral condensate. | eng_Latn | 26,586 |
Negative resistance and the development of the Gunn effect oscillator | Progress in the understanding of negative resistance led to the concept of a Gunn oscillator, but realization of the device awaited development in GaAs technology. Device technology then increased rapidly. Most noticeable development lay in cavity operation, Frequency control, and LSA mode operation. Finally, the applications of the devices are reviewed. | A general expression is constructed for the weak hadronic current in the colored-quark model with SU (3) x SU (3) ' symmetry. It is shown that there exist several different solutions for which it is possible to suppress neutral currents with changing strangeness. An additional peculiarity of the model is the presence of ..delta..Q=2 transitions which also result in diagonal neutral currents. | eng_Latn | 26,587 |
Isovector proton-neutron pairing and Wigner energy in Hartree-Fock mean field calculations | We propose a new approach for the treatment of isovector pairing in self-consistent mean field calculations which conserves exactly the isospin and the particle number in the pairing channel. The mean field is generated by a Skyrme-HF functional while the isovector pairing correlations are described in terms of quartets formed by two neutrons and two protons coupled to the total isospin T=0. In this framework we analyse the contribution of isovector pairing to the symmetry and Wigner energies. It is shown that the isovector pairing provides a good description of the Wigner energy, which is not the case for the mean field calculations in which the isovector pairing is treated by BCS-like models. | We describe preliminary results from an effort to quantify the uncertainties in parton distribution functions and the resulting uncertainties in predicted physical quantities. The production cross section of the $W$ boson is given as a first example. Constraints due to the full data sets of the CTEQ global analysis are used in this study. Two complementary approaches, based on the Hessian and the Lagrange multiplier method respectively, are outlined. We discuss issues on obtaining meaningful uncertainty estimates that include the effect of correlated experimental systematic uncertainties and illustrate them with detailed calculations using one set of precision DIS data. | eng_Latn | 26,588 |
235U Holdup Measurements in the 321-M Cooling Hut HEPA Bank | This report covers holdup measurements of uranium residue in the cooling hut HEPA bank of the 321-M facility. This report discusses the methodology, non-destructive assay measurements, assumptions, and results of the uranium holdup in this item. | The last few years, 2013-2016, the high energy neutrino events in ICECUBE and the last rich UHECR maps by AUGER and TA were hopefully opening a new High Energy astronomy age. Unfortunately the foreseen correlation between neutrino with best gamma X sources has not (yet) been found. The most celebrated GRB gamma sources do not correlate to any neutrino events. The expected Local Group anisotropy in UHECR within the nuleon GZK cut off, has just fade away. UHECR events from Virgo are almost absent. Above two hundred TeV energy tau neutrino might shine by double bang in detectable way in ICECUBE. Within a dozen of events no tau neutrino arised (yet) in ICECUBE. Finally GRBs Fireball models calling since decades for HE neutrinos correlated imprint at TeVs energy are not (yet) found. So many absences are making a huge question mark: is there a new reading key? | eng_Latn | 26,589 |
Saturation in Deuteron Hadamard NMR Spectroscopy of Solids | Abstract Hadamard NMR was investigated for wide-line solid-state deuteron spectroscopy by numerical simulations and experiments on hexamethylbenzene. Similar signal-to-noise ratios were obtained at large filter bandwidths (500 kHz) by both the quadrupolar echo and the Hadamard methods, although the excitation power differs by up to four orders in magnitude. Increasing the excitation power leads to systematic, noise-like features in Hadamard spectra. In contrast to phase modulation, simulations indicate that for amplitude modulation of the pseudorandom excitation, the pulse sequence burns a saturation hole into the lineshape at the carrier frequency. Violation of the cyclicity requirement by introduction of a recycle delay between successive Hadamard scans results in a high-frequency noise contribution. Finite pulse widths are shown not to cause significant spectral distortions. | We study the processes $e^+ e^- \to Y(4260) \to J/\psi \pi\pi(K\bar{K})$. The strong final-state interactions, especially the coupled-channel ($\pi\pi$ and $K\bar{K}$) final-state interaction in the $S$-wave are taken into account in a model-independent way using dispersion theory. It is found that the light-quark SU(3) octet state plays a significant role in these transitions, implying that the $Y(4260)$ contains a large light-quark component. Our findings suggest that the $Y(4260)$ is neither a hybrid nor a conventional charmonium state. Furthermore, through an analysis of the ratio of the light-quark SU(3) octet and singlet components, we show that the $Y(4260)$ does not behave like a pure $\bar D D_1$ hadronic molecule as well. | eng_Latn | 26,590 |
Symmetry and concentration behavior of ground state in axially symmetric domains | We let Ω(r) be the axially symmetric bounded domains which satisfy some suitable conditions, then the ground-state solutions of the semilinear elliptic equation in Ω(r) are nonaxially symmetric and concentrative on one side. Furthermore, we prove the ::: necessary and sufficient condition for the symmetry of ground-state solutions. | Measurements performed at the Tevatron of both the like-sign dimuon charge asymmetry inBd;s-meson samples and the mixing-induced CP asymmetry inBs! J= depart from their standard model (SM) predictions. This could be an indication for new CP phases in B = 2 transitions, preferentially in Bs{ Bs mixing. The experimental situation, however, remained inconclusive, as it favored values of the element s of the decay matrix in the Bs-meson system that are notably dierent | eng_Latn | 26,591 |
Minijets: Cross section and energy distribution in very-high-energy nuclear collisions. | The energy spectrum from semihard partonic interactions in nucleus-nucleus collisions with c.m. energies of the order of 1 TeV per nucleon is discussed. The presence of a large number of nucleons induces incoherence among most of the partonic collisions, while the large number of partonic interactions makes the unitarization of the cross section an essential tool for a meaningful description of the processes. This goal is achieved, accounting for all semihard partonic scatterings, namely, including both disconnected collisions and rescatterings. The characteristic feature of the interaction resulting from this analysis is that it is basically a geometrical one. As a consequence of the unitarization, the energy distribution of the scattered partons turns out to be a regular function of the cutoff {ital p}{sub {ital t}}{sup min} which separates semihard events from soft ones. | We propose a simple scheme to start a parton-shower evolution description from a given jet configuration in ${e}^{+}{e}^{\ensuremath{-}}$ annihilation events. This allows a convenient combination of the full angular information content of matrix elements with the detailed sub-jet structure of parton showers, and should give a realistic overall description of event properties. Explicit studies with this hybrid approach are presented for the four-jet case, as a simple testing ground of the ideas. | eng_Latn | 26,592 |
Indirect bounds on the Higgs boson mass from precision electroweak data | We discuss the masses of the top quark and of the Higgs boson in the light of the available precision electroweak data, considering the latest LEP data as well as the latest CCFR measurements of νN and the SLC measurement of the left-right polarization asymmetry. The high precision reached by the experiments makes now possible to observe for the first time some discrepancies between different sets of data. In particular, the values of mt indicated by different subsets of data differ by about 1.3 standard deviations, and the present direct experimental limit on the Higgs mass is somewhat higher than the indirect indications about its mass from the radiative correction effects. Ignoring these discrepancies, we find mt < 155 GeV, MH < 250 GeV, each at the 95% confidence level, from the precision electroweak data alone. | In this paper , we study some approximation properties of the strong difference and study the relation between the strong difference and the weighted modulus of continuity | eng_Latn | 26,593 |
Can collisional energy loss explain nuclear suppression factor for light hadrons | We argue that in the measured $p_T$ domain of RHIC, collisional rather than the radiative energy loss is the dominant mechanism for jet quenching. Accordingly we calculate nuclear suppression factor for light hadrons by taking only the elastic energy loss in sharp contrast with the previous calculations where only the radiative loss are considered. | We have studied segregation and embrittling energy of sp ::: elements of the 3rd, 4th and 5th period (Al, Si, P, S, Ga, Ge, ::: As, Se, In, Sn, Sb and Te) at the Sigma5(210) grain boundary ::: (GB) in fcc nickel and the segregation of these impurities at ::: the (210) free surface (FS). Full relaxation of the geometric ::: configuration of the GB and FS without and with impurities has ::: been performed and the effect of impurities on the distribution ::: of magnetic moments has been analysed. We determined the ::: embrittling energy from the difference between the GB and FS ::: binding energies on the basis of the Rice Wang model. and we ::: separated embrittling energy into the chemical and mechanical ::: part. | eng_Latn | 26,594 |
Unquenching the scalar glueball | Computations in the quenched approximation on the lattice predict the lightest glueball to be a scalar in the 1.5−1.8 GeV region. Here we calculate the dynamical effect the coupling to two pseudoscalars has on the mass, width and decay pattern of such a scalar glueball. These hadronic interactions allow mixing with the qq scalar nonet, which is largely fixed by the well-established K ∗ 0 (1430). This non-perturbative mixing means that, if the pure gluestate has a width to two pseudoscalar channels of ∼ 100 MeV as predicted on the lattice, the resulting hadron has a width to these channels of only ∼ 30 MeV with a large �� component. Experimental results need to be reanalyzed in the light of these predictions to decide if either the f0(1500) or an f0(1710) coincides with this dressed glueball. | Abstract In the 6D brane world model with a 4-form flux on a sphere S 2 for self-tuning the cosmological constant, we comment on the fine-tuning problem in view of the quantization of the dual 2-form flux and the orbifolding case S 2 / Z 2 . | eng_Latn | 26,595 |
Stability Analysis in a Class of Stage Structure SIS Model with Small Delay | In this paper,the stability of a class of stage structure SIS model with small delay is studied.The sufficient conditions for asymptotical stability of the equilibrium are given.Some simulations are carried out by matlab software to support the correctness of our analysis results.Owing to the small delay,the results are the continuation and complement of the previous authors. | We study spatial correlation functions of static quark-antiquark pairs in QCD with 2+1 flavors in order to better understand color screening at high temperatures. ::: We performed lattice simulations in a wide temperature window $115\,{\rm MeV}\lesssim T\lesssim 5.8\,{\rm GeV}$ using the using the highly improved staggered quark (HISQ) action, the tree-level improved Symanzik gauge action and several lattice spacings to control discretization effects. ::: By comparing our lattice results to analytic calculations at weak coupling as well as to the zero temperature result on the static energy we demonstrate that color screening sets in at distances $rT \simeq 0.25$. ::: We also conclude that in the distance regime $0.25<r T< 0.6$ the weak-coupling approach provides an adequate description of color screening. | kor_Hang | 26,596 |
The triplet state IR spectrum of matrix-isolated anthracene | Abstract The lowest triplet state infrared spectrum of matrix-isolated anthracene between 1650 and 550 cm−1 is reported. The seven triplet state bands were tentatively assigned based on frequency proximity to ground state absorptions and comparisons with triplet state features in similar molecules. | We discuss some recent phenomenological models for strong interactions based on the idea of gauge/string duality. A very good estimate for hadronic masses can be found by placing an infrared cut off in AdS space. Considering static strings in this geometry one can also reproduce the phenomenological Cornell potential for a quark anti-quark potential at zero temperature. Placing static strings in an AdS Schwarzschild space with an infrared cut off one finds a transition from a confining to a deconfining phase at some critical horizon radius (associated with temperature). | eng_Latn | 26,597 |
Semiclassical quantization of a nonintegrable system: Pushing the Fourier method into the chaotic regime | Semiclassical Einstein–Brillouin–Keller (EBK) quantization of the nonintegrable Henon–Heiles Hamiltonian succeeds using the Fourier transform method of Martens and Ezra. Two innovations are required for this success: (1) the use of tunneling corrected quantizing actions obtained from an approximate, one‐dimensional Hamiltonian and (2) exploitation of intermediate‐time approximate quasiperiodicity or ‘‘vague tori’’ wherein the Fourier transform of chaotic motion over 10–100 vibrational periods allows the determination of frequencies and amplitudes which approximate motion during the time interval. Approximate tori, actions, and EBK energy levels are then straightforward. We use an interpolation method to smooth over small resonance zones that are not expected to be important quantum mechanically. | We study the processes $e^+ e^- \to Y(4260) \to J/\psi \pi\pi(K\bar{K})$. The strong final-state interactions, especially the coupled-channel ($\pi\pi$ and $K\bar{K}$) final-state interaction in the $S$-wave are taken into account in a model-independent way using dispersion theory. It is found that the light-quark SU(3) octet state plays a significant role in these transitions, implying that the $Y(4260)$ contains a large light-quark component. Our findings suggest that the $Y(4260)$ is neither a hybrid nor a conventional charmonium state. Furthermore, through an analysis of the ratio of the light-quark SU(3) octet and singlet components, we show that the $Y(4260)$ does not behave like a pure $\bar D D_1$ hadronic molecule as well. | eng_Latn | 26,598 |
Effective Lagrangian and equations for valence quark and gluon Green's functions | Starting from the QCD Lagrangian and separating background and valence degrees of freedom, one arrives at the effective Lagrangian for valence quarks and gluons. Each term in the Lagrangian contains a product of valence quark and gluon operators acting at the end of the fundamental or adjoint string, made of the background field. A simple procedure is described how to obtain from the Lagrangian self-coupled equations for quark and gluon Green's function. | Abstract A self-consistent quasilinear model of the interaction between VLF emissions and geomagnetic pulsation is set forth. As a result an explicit expression of a modulation frequency dependence can be obtained. | eng_Latn | 26,599 |
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