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A critical evaluation of the equivalent-energy method | Abstract A critical evaluation of the equivalent-energy method in fracture mechanics analysis is presented. The author concludes that the equivalent-energy method is predicated on assumptions which are very restrictive and preclude its use as a general method and that the method does not yield valid results in the analysis of flawed tensile specimens. | We compute the O(alpha_t alpha_s) two-loop corrections to the neutral Higgs boson masses in the Minimal Supersymmetric extension of the Standard Model. An appropriate use of the effective potential allows us to obtain simple analytical formulae, valid for arbitrary values of mA and of the mass parameters in the stop sector. We elucidate some subtleties of the effective potential calculation, and find full agreement with the numerical output of the existing diagrammatic calculation. We discuss in detail the limit of heavy gluino. | eng_Latn | 26,700 |
Skladovací procesy a jejich optimalizace ve společnosti ČEZ, a. s. | The thesis is focus on the optimization storage process, on storage management and there are some practical solutions for the company CEZ | 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. | ces_Latn | 26,701 |
Critical Higgs Mass for the (2+1)-dimensional Georgi-glashow Model | Abstract The ground state of a (2+1) dimensional Georgi-Glashow model is discussed in a dilute monopole gas approximation. In addition to the Coulomb interaction of the latter, we include a Higgs force which is attractive irrespective of the sign of monopole charges. For (Higgs masses) −1 comparable to the mean free distance of monopoles we find a phase transition which is presumably of first order. Strings of monopoles dominate the clustering behaviour near the critical Higgs mass. | 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 | 26,702 |
Constituent quarks and total cross sections at LHC/SSC | Abstract A constituent quark model is shown to describe the phenomenology of σ tot and the elastic d σ /d t at high energy in a natural way. Multiple scattering is found to be important. The model is used to predict σ tot and the forward elastic slope B at energies of the LHC and SSC colliders. The predicted σ tot is smaller than in most other models. Cross sections for single-diffractive scattering are also predicted. | The superluminal radio components observed in microquasars are usuallyinterpreted as individual ejection events. We discuss some of theshortcomings of this model and propose the internal shock model inquasi-continuous relativistic jets as an alternative. This model canresolve the problems with the single ejection model and is inagreement with radio observations. We outline some further testablemodel predictions some of which are already confirmed by observations. | eng_Latn | 26,703 |
Chromodynamic Structure and Phenomenology | In these three lectures, I will discuss some of the formal and phenomenological features of quantum chromodynamics (QCD). This local gauge theory based on the color group SU(3) has stood as probably the most attractive candidate for a theory of strong interactions since the discovery of asymptotic freedom in 1973. There has been an enormous amount of theoretical work since then learning how to confront the theory with experiment in the short distance, weak coupling regime and trying to deal with the theory at larger distances(say 1/mπ) where it presumably becomes strongly coupled. | Recent theoretical and experimental work on helically twisted photonic crystal fibres (PCFs) is reviewed. Helical Bloch theory is introduced, including a new formalism based on the tight-binding ap... | kor_Hang | 26,704 |
Mixed QCD-EW corrections for Higgs boson production at $e^+e^-$ colliders | Since the discovery of the Higgs boson at the Large Hadron Collider, a future electron-position collider has been proposed for precisely studying its properties. We investigate the production of the Higgs boson at such an $e^+e^-$ collider associated with a $Z$ boson, and calculate for the first time the mixed QCD-electroweak corrections to the total cross sections. We provide an approximate analytic formula for the cross section and show that it reproduces the exact numeric results rather well for collider energies up to 350 GeV. We also provide numeric results for $\sqrt{s}=500$ GeV, where the approximate formula is no longer valid. We find that the $\mathcal{O}(\alpha\alpha_s)$ corrections amount to a 1.3% increase of the cross section for a center-of-mass energy around 240 GeV. This is significantly larger than the expected experimental accuracy and has to be included for extracting the properties of the Higgs boson from the measurements of the cross sections in the future. | In this paper lower bounds are obtained for quasi-local masses in terms of charge, angular momentum, and horizon area. In particular we treat three quasi-local masses based on a Hamiltonian approach, namely the Brown-York, Liu-Yau, and Wang-Yau masses. The geometric inequalities are motivated by analogous results for the ADM mass. They may be interpreted as localized versions of these inequalities, and are also closely tied to the conjectured Bekenstein bounds for entropy of macroscopic bodies. In addition, we give a new proof of the positivity property for the Wang-Yau mass which is used to remove the spin condition in higher dimensions. Furthermore, we generalize a recent result of Lu and Miao to obtain a localized version of the Penrose inequality for the static Wang-Yau mass. | eng_Latn | 26,705 |
Generation of high-voltage pulses in a self-oscillating discharge | The possibility of generation of high-voltage pulses in the self-oscillation mode of a beam-plasma discharge is shown. Negative voltage pulses with amplitudes of up to 40 kV are recorded at the plasma facing electrode at a constant negative bias voltage of 200–300 V. | We analyze a 2+1-dimensional model with charged, relativistic fermions interacting through a four-Fermi term and a fluctuating gauge field. Taking advantage of its large-N renormalizability, the various phases of this model are studied at finite temperature and beyond the leading order in 1/N. In the absence of gauge-field interaction, severe infrared divergences forbid spontaneous breaking of U(1) symmetry. Although the thermal vacuum expectation value of a charged order parameter is zero, the model nevertheless exhibits a quasi-long-range order due to the nontrivial dynamics of the vortex excitations on the plane. When the gauge field is dynamical, we show that the infrared divergences disappear and the mechanism of superconductivity is set by the spontaneous breaking of U(1) symmetry. | eng_Latn | 26,706 |
Instanton Triggered Chiral Symmetry Breaking, the U(1) Problem and a Possible Solution to the Strong CP Problem | We argue that instantons play a crucial role in triggering the spontaneous breaking of chiral symmetry in the physics of the three light quarks in quantum chromodynamics. However, instantons may also play an essential role in our understanding of the suppression of CP violation in the strong interactions. We revive the possibility that the bare mass of the up quark is identically zero and the apparent small up quark mass is generated by the effective quark dynamics associated with instantons. In this case, the strong CP phase becomes unobservable and there is no strong CP violation. | A power-counting renormalizable model into which massive Yang-Mills theory is embedded is analyzed. The model is invariant under a nilpotent BRST differential s. The physical observables of the embedding theory, defined by the cohomology classes of s in the Faddeev-Popov neutral sector, are given by local gauge-invariant quantities constructed only from the field strength and its covariant derivatives. | eng_Latn | 26,707 |
Breaking rotational symmetry in two-flavor color superconductors | The color superconductivity under flavor asymmetric conditions relevant to compact star phenomenology is studied within the Nambu\char21{}Jona-Lasinio model. We focus on the effect of the deformation of the Fermi surfaces on the pairing properties and the energy budget of the superconducting state. We find that at finite flavor asymmetries the color superconducting BCS state is unstable towards spontaneous quadrupole deformation of the Fermi surfaces of the d and u quarks into ellipsoidal form. The ground state of the phase with deformed Fermi surfaces corresponds to a superposition of prolate and oblate deformed Fermi ellipsoids of d and u quarks. | 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 | 26,708 |
LETTER On the Balanced Elementary Symmetric Boolean Functions | SUMMARY In this paper, we give some results towards the conjecture that σ 2t+1l−1,2t are the only nonlinear balanced elementary symmetric Boolean functions where t and l are positive integers. At first, a unified and simple proof of some earlier results is shown. Then a property of balanced elementary symmetric Boolean functions is presented. With this property, we prove that the conjecture is true for n = 2 m + 2 t − 1w herem,t(m > t )a re two non-negative integers, which verified the conjecture for a large infinite | 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 | 26,709 |
Observation of a Narrow Charm-Strange MesonDsJ+(2632)→Ds+ηandD0K+ | We report the first observation of a charm-strange meson D(+)(sJ)(2632) at a mass of 2632.5+/-1.7 MeV/c(2) in data from SELEX, the charm hadro-production experiment E781 at Fermilab. This state is seen in two decay modes, D(+)(s)eta and D0K+. In the D(+)(s)eta decay mode we observe a peak with 101 events over a combinatoric background of 54.9 events at a mass of 2635.4+/-3.3 MeV/c(2). There is a corresponding peak of 21 events over a background of 6.9 at 2631.5+/-2.0 MeV/c(2) in the decay mode D0K+. The decay width of this state is <17 MeV/c(2) at 90% confidence level. The relative branching ratio Gamma(D0K+)/Gamma(D(+)(s)eta) is 0.14+/-0.06. The mechanism that keeps this state narrow is unclear. Its decay pattern is also unusual, being dominated by the D(+)(s)eta decay mode. | We present the Penrose limits of a complex marginal deformation of $AdS_5\times S^5$, which incorporates the $SL(2,\mathbb{R})$ symmetry of type IIB theory, along the $(J,0,0)$ geodesic and along the $(J,J,J)$ geodesic. We discuss giant gravitons on the deformed $(J,0,0)$ pp-wave background. | eng_Latn | 26,710 |
2013-2016 review: HE Neutrino and UHECR Astronomy? | 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? | The situations of conflict in Central Queensland University and Bond University between the staff and the Government over grant of funds are presented. Efforts made by the NTEU in bargaining for the members' rights with respect to the Higher Education Workplace Relations Requirements (HEWRRs) are discussed. | kor_Hang | 26,711 |
1 Simulating dynamical fermions with smeared links | Abstract Recently we proposed the hypercubic smearing (HYP) that improves the flavor symmetry of staggered fermions by an order of magnitude with only minimal distortions at small distances. We describe a new algorithm to simulate dynamical HYP fermions based on the standard pure gauge overrelaxation and heatbath updates. The algorithm has been used to simulate four and two flavors of staggered fermions. Unlike standard dynamical simulation techniques, this algorithm does not loose efficiency at small quark masses. | The authors construct periodic interpolating wavelets and their duals from a periodio ftmction g(x) whose Fourier coefficiente are positive. The corresponding decomposition and reconstructlon algorithm is also given. The spline example shows that such kind of wavelets shares good localization with any desired regularity and symmetry. The constructlon dependsessentially on the finite Fourier Transformation and the theory of circulant matrix. | eng_Latn | 26,712 |
Final-state QED Multipole Radiation in Antenna Parton Showers | We present a formalism for a fully coherent QED parton shower. The complete multipole structure of photonic radiation is incorporated in a single branching kernel. The regular on-shell 2 to 3 kinematic picture is kept intact by dividing the radiative phase space into sectors, allowing for a definition of the ordering variable that is similar to QCD antenna showers. A modified version of the Sudakov veto algorithm is discussed that increases performance at the cost of the introduction of weighted events. Due to the absence of a soft singularity, the formalism for photon splitting is very similar to the QCD analogon of gluon splitting. However, since no color structure is available to guide the selection of a spectator, a weighted selection procedure from all available spectators is introduced. | 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 | 26,713 |
Global warming could increase the chances of Leptospira infection | As a result of continuing climate change, heightened awareness of leptospirosis in temperate regions is warranted, German researchers say. | 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 | 26,714 |
Intersection theorems and their applications in general almost convex spaces | Abstract In this paper, we extend the concept of the almost convex condition and establish an approximation property for convex continuous correspondences. We use the approximation property to generalize von Neumann’s intersection theorems and related topics. We obtain, as applications, some new equilibrium theorems for the existence of a maximal element, generalized games, and qualitative games of U -majorized correspondences. | We study factorization schemes for parton shower models in hadron-hadron collisions. As an example, we calculate lepton pair production mediated by a virtual photon in quark--anti-quark annihilation, and we compare factorized cross sections obtained in the conventional $\bar{\rm MS}$ scheme with those obtained in a factorization scheme in which a kinematical constraint due to parton radiation is taken into account. We discuss some properties of factorized cross sections. | eng_Latn | 26,715 |
Transverse mass distributions of neutral pions from $^{208}$ Pb-induced reactions at 158 $\cdot A$ GeV | Results on transverse mass spectra of neutral pions measured at central rapidity are presented for impact parameter selected 158$\cdot A$ GeV Pb + Pb, and Pb + Nb collisions. The distributions cover the range $0.5 \mathrm{GeV}/c^{2} \le m_{T} - m_{0} \le 4 \mathrm{GeV}/c^{2}$. The change of the spectral shape with centrality is studied in detail. In going from peripheral to medium central collisions there is a nuclear enhancement increasing with transverse mass similar to the well known Cronin effect, while for very central collisions this enhancement appears to be weaker than expected. | We study in this paper the properties of a two-body random matrix ensemble for distinguishable spins. We require the ensemble to be invariant under the group of local transformations and analyze a parametrization in terms of the group parameters and the remaining parameters associated with the 'entangling' part of the interaction. We then specialize to a spin chain with nearest-neighbour interactions and numerically find a new type of quantum-phase transition related to the strength of a random external field, i.e. the time-reversal-breaking one-body interaction term. | eng_Latn | 26,716 |
Suppression ofJ/ψandψ′production in high-energy Pb on Pb collisions | The anomalous J/psi suppression in Pb-Pb collisions at 158A GeV observed recently by NA50 can be explained as due to the transition to a new phase of strong J/psi absorption, which sets in when the local energy density exceeds about 3.4 GeV/fm**3. | Using $sup 4$He as an example, it is shown that in the reaction ($pi$$sup -$, nn) the pion rescattering effect plays a decisive role at small momentum transfers, while the effective exchange between all nucleons in the final state plays a major role at large transfers. This leads to the appearance of corresponding two maxima, in agreement with the recently obtained experimental data. | eng_Latn | 26,717 |
NLO Higgs boson production via vector-boson fusion matched with shower in POWHEG | We present a next-to-leading order calculation of Higgs boson production in vector-boson fusion processes interfaced to shower Monte Carlo programs, implemented according to the POWHEG method. | When the gas turbine to use heavy fuel oil, the ash matter cover HRSG (Heat Recovery Steam Generator) in the tube wall. How to deal with the ash matter is direct to influence the combined cycle power plant upon safety and economy. Shakou Power Plant , Foshan, Guangdong has adopted some ways to deal with the ash matter. The HRSG has kept its good safety and economy operation more than 9 year. | eng_Latn | 26,718 |
Improved particle confinement in transition from multiple-helicity to quasi-single-helicity regimes of a reversed-field pinch. | The quasi-single-helicity (QSH) state of a reversed-field pinch (RFP) plasma is a regime in which the RFP configuration can be sustained by a dynamo produced mainly by a single tearing mode and in which a helical structure with well-defined magnetic flux surfaces arises. In this Letter, we show that spontaneous transitions to the QSH regime enhance the particle confinement. This improvement is originated by the simultaneous and cooperative action of the increase of the magnetic island and the reduction of the magnetic stochasticity. | The neutrinoproduction of $\phi$ and $D^+_s$ mesons is studied, using the data obtained with the SKAT bubble chamber at the Serpukhov accelerator. It is found that the $\phi$ production occurs predominantly in the forward hemisphere of the hadronic c.m.s. (at $x_F > 0$, $x_F$ being the Feynman variable), with the mean yield strongly exceeding the expected yield of directly produced $\phi$ mesons and varying from $ 0) > = (0.92\pm0.34) \cdot 10^{-2}$ at $W > $ 2 GeV up to $(1.23\pm0.53) \cdot 10^{-2}$ at $W >$ 2.6 GeV and $(1.44\pm0.69) \cdot 10^{-2}$ at $W >$ 2.9 GeV, $W$ being the invariant mass of the hadronic system. The yield of leading $D^+_s$ mesons carrying more than $z = 0.85$ of the current $c$- quark energy is estimated: at $W > 2.9$ GeV, $ 0.85) > = (6.64\pm1.91) \cdot 10^{-2}$. It is shown, that the shape of the $\phi$ meson differential spectrum on $x_F$ is reproduced by that expected from the $D^+_s \to \phi X$ decays which, however, can account for only the half of the measured $\phi$ yield. | eng_Latn | 26,719 |
P-signal complexity and upper mantle structure | Summary. Data do not support earlier suggestions that absorption along the path of the direct P signal relative to later arrivals is responsible for variations in the complexity of P signals from nuclear explosions. Scattering of seismic waves in the crust and upper mantle explains many aspects of the P coda and we suggest that complexity is a function, not of variation in attenuation for paths between source and station, but of the scattering properties of the upper mantle. | 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 | 26,720 |
Symmetry and classes of transport equations | A method for classification and determination of local transport equations is presented based on the use of Lie symmetries. The starting point is the choice of a specific symmetry group and the definition of a class of partial-differential equations. Results associated with the Fokker–Planck equation in (1+1) and (2+1) dimensions are given. | 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 | 26,721 |
Uz pieradijumiems balstita prakse: principi, process, politika, standarti. | Translation into Latvian of Chapter 1, Evidence-based practice: principles, process, policy and proof from Art Therapy, Research and Evidence Based Practice, published by Sage Publications, London in 2006. | 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. | lvs_Latn | 26,722 |
Explanation of the formation dynamics of the bound state with ion implantation | Taking into account the structure and the size of localized electrons the density matrix of localized electrons is analytically derived. In the framework of Kohn's approximation the analytical expression is used for the density matrix, and the additional potential for the three-body Coulomb systems is determined. Our result shows that, the consideration of the structure and size of localized electrons leads to an additional potential. If the size parameter is small, then the additional potential is the oscillator one. This gives a possibility to explain experimental 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 | 26,723 |
NNLL resummation for the associated production of a top pair and a Higgs boson at the LHC | We study the resummation of soft gluon emission corrections to the production of a top-antitop pair in association with a Higgs boson at the Large Hadron Collider. Starting from a soft-gluon resummation formula derived in previous work, we develop a bespoke parton-level Monte Carlo program which can be used to calculate the total cross section along with differential distributions. We use this tool to study the phenomenological impact of the resummation to next-to-next-to-leading logarithmic (NNLL) accuracy, finding that these corrections increase the total cross section and the differential distributions with respect to NLO calculations of the same observables. | This paper incorporates labor search frictions into a model with lumpy capital to explain a set of stylized facts about the United States labor market dynamics over business cycles. All of these facts are related to …rm size: (1) job creation is procyclical in both small and large …rms; (2) job destruction is countercyclical in large …rms, but, paradoxically, it is procyclical in small …rms; and (3) job creation and job destruction are more volatile in large …rms than in small …rms. The model is calibrated to US data and its predictions are broadly consistent with the facts. The success of the model relies on the interaction between labor search and lumpy capital. Search frictions imply that even if two …rms have the | eng_Latn | 26,724 |
A Tale of Two Systems: Resonator Structures and Coupled Quantum Wells | Periodic arrays of microresonators coupled to channel waveguides, and Bragg stacks of quantum wells, are two drastically different physical systems that exhibit the same dispersion relation. Similarities and differences in their optical properties are presented. | Bottom-up holographic models of QCD, inspired by the anti-de Sitter space/conformal field theory correspondence, have shown a remarkable degree of phenomenological success. However, they rely on a number of bold assumptions. We investigate the reliability of one of the key assumptions, which involves matching the parameters of these models to QCD at high 4D momentum q{sup 2} and renormalization scale {mu}{sup 2}. We show that this leads to phenomenological and theoretical inconsistencies for scale-dependent quantities such as . | eng_Latn | 26,725 |
A matching of matrix elements and parton showers | 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. | 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 | 26,726 |
Nonuniformly driven two-plasmon-decay instability in direct-drive implosions. | Half-harmonic emission spectra and images taken during directly driven implosions show that the two-plasmon decay (TPD) instability is driven nonuniformly over the target surface and that multibeam effects dominate this instability. The images show a spatially limited extent of the TPD instability. A prominent spectral feature is used to determine the electron temperature in the corona. Near threshold the temperatures agree with one-dimensional hydrodynamic predictions but exceed them by ∼10% above the TPD threshold. Two-dimensional hydrodynamic simulations indicate that a significant part (∼20%) of the laser intensity must be locally absorbed by the TPD instability (i.e., by collisional damping of the electron plasma waves) to maintain these temperature islands. | 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 | 26,727 |
Proton-rich unstable nuclei in explosive hydrogen burning | Abstract Onset of the rapid-proton process is discussed based on the recent experimental data of proton-rich unstable nuclei. A new experimental result on the Ne-E problem is also discussed. The low-energy radioactive nuclear beam project at INS is briefly reported that is under construction for nuclear astrophysics. | 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 | 26,728 |
Generation of Raman dissipative solitons near 13 microns in a phosphosilicate-fiber cavity | An external-cavity generation of powerful ultrashort pulses in an all-fiber scheme by using a new type of phosphosilicate polarization maintaining fiber is investigated. The phosphorus-related Stokes shifted Raman pulse near 1.3 microns is observed. Optimization of Stokes output spectrum depending on pump pulse duration (chirp), energy and output coupling ratio of the cavity is performed. As result, the output energy of highly-chirped pulses compressible to 570 fs reaches 1.6 nJ. | Abstract We extend our model for the pion, which we used previously to calculate its diagonal structure function, to the off-forward case. The imaginary part of the off-forward γ★π→γ★π scattering amplitude is evaluated in the chiral limit (mπ=0) and related to the twist-two and twist-three generalised parton distributions H, H3, H 3 . Non-perturbative effects, linked to the size of the pion and still preserving gauge invariance, are included. Remarkable new relations between H, H3 and H 3 are obtained and discussed. | eng_Latn | 26,729 |
NASA-Industry Team Creates First Quantum Sensor for Gravitometry | NASA and the Sunnyvale, California-based AOSense, Inc., have successfully built and demonstrated a prototype quantum sensor capable of obtaining highly sensitive and accurate gravity measurements — a stepping stone toward next-generation geodesy, hydrology, and climate-monitoring missions in space | 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). | kor_Hang | 26,730 |
Peer Reviewed Title: Disentangling the body weight-bone mineral density association among breast cancer survivors: an examination of the independent roles of lean mass and fat mass | Abstract Background Bone mineral density (BMD) and lean mass (LM) may both decrease in breast cancer survivors, thereby increasing risk of falls and fractures. Research is needed to determine whether lean mass (LM) and fat mass (FM) independently relate to BMD in this patient group. Methods The Health, Eating, Activity, and Lifestyle Study participants included 599 women, ages 29–87 years, diagnosed from 1995–1999 with stage 0- IIIA breast cancer, who underwent dual-energy X-ray absorptiometry scans approximately 6- months postdiagnosis. We calculated adjusted geometric means of total body BMD within quartiles (Q) of LM and FM. We also stratified LM-BMD associations by a fat mass index threshold that tracks with obesity (lower body fat: ≤12.9 kg/m2; higher body fat: >12.9 kg/m2) and stratified FM-BMD associations by appendicular lean mass index level corresponding with sarcopenia (non-sarcopenic: ≥ 5.45 kg/ | Thermal leptogenesis and supergravity are attractive scenarios for physics beyond the standard model. However, it is well known that the super-weak interaction of the gravitino often leads to problems with primordial nucleosynthesis in the standard scenario of matter parity conserving MSSM + three right-handed neutrinos. We will present and compare two related solutions to these problems: 1) The conflict between BBN and leptogenesis can be avoided in presence of a hidden sector with light supersymmetric particles which open new decay channels for the dangerous long-lived particles. 2) If there is a condensate in the hidden sector, such additional decay channels can be alternatively opened by dynamical breaking of matter parity in the hidden sector. | eng_Latn | 26,731 |
Particle Physics in the Cosmos: Session Summary | This manuscript presents a summary on the parallel session V "Particles in the Cosmos" of the Neutrino Oscillation Workshop -- NOW 2018. The topics covered by the session are a combination of new theoretical approaches and ideas and a selection of recent experimental results and upcoming projects. | The latest results from ATLAS and CMS on single top quark production and rare production channels of top quarks at the LHC are presented. | eng_Latn | 26,732 |
Evolving dark energy with w not = -1. | Theories of evolving quintessence are constructed that generically lead to deviations from the w = -1 prediction of nonevolving dark energy. The small mass scale that governs evolution, m(phi) approximately = 10(-33) eV, is radiatively stable, and the "Why now?" problem is solved. These results rest on seesaw cosmology: Fundamental physics and cosmology can be broadly understood from only two mass scales, the weak scale nu and the Planck scale M. Requiring a scale of dark energy rho(DE)(1/4) governed by nu2/M and a radiatively stable evolution rate m(phi) given by nu4/M3 leads to a distinctive form for the equation of state w(z). Dark energy resides in the potential of a hidden axion field that is generated by a new QCD-like force that gets strong at the scale lambda approximately = nu2/M approximately = rho(DE)(1/4). The evolution rate is given by a second seesaw that leads to the axion mass m(phi) approximately = lambda2/f, with f approximately = M. | By using the technique of integration within an ordered product (IWOP) of operator we derive Wigner function of density operator for negative binomial distribution of radiation field in the mixed state case, then we derive the Wigner function of squeezed number state, which yields negative binomial distribution by virtue of the entangled state representation and the entangled Wigner operator. | eng_Latn | 26,733 |
BUHEP-99-15 Triviality and the Precision Bound on the Higgs Mass | Abstract The triviality of the scalar sector of the standard one-doublet Higgs model implies that this model is only an effective low-energy theory valid below some cut-off scale Λ . For a heavy Higgs this scale must be relatively low (10 TeV or less). Additional interactions coming from the underlying theory, and suppressed by the scale Λ , give rise to model-dependent corrections to precisely measured electroweak quantities. Dimension six operators arising from the underlying physics naturally contribute to the S and T parameters, and their effects should be included in a global fit to the precision data that determines any limit on the Higgs mass. Using dimensional analysis, we estimate the expected size of these corrections in a custodially-symmetric strongly-interacting underlying theory. Taking these operators' coefficients to be of natural size gives sufficiently large contributions to the T parameter to reconcile Higgs masses as large as 400–500 GeV with the precision data. | This short note discusses various errors in the Bouguer reduction that have been discussed recently in the literature. It also discusses two other errors arising out of the “indirect effect” and the uncertainty in the value of the universal constant of gravitation, G, that previously have not been discussed extensively in the literature. | eng_Latn | 26,734 |
Physical Explanation to SU UMa-type Dwarf Nova's Explosion and Super-explosion | Su UMa-type dwarf novas belong to cataclysmic variable stars, whose character is magnified explosion, i.e., super-explosion. This article gives the physical explanation to SU Uma-type dwarf nova's explosion and super-explosion. | 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 | 26,735 |
The Production and Use of an NIST-Traceable Standard Solution for Quantitative NMR Applications | The concentration of the benzoic acid (m b ) in the solution is calculated by dividing the mass fraction corrected weight of the benzoic acid by the total weight of the solution. The uncertainty calculation incorporates the appropriate weight and mass fraction uncertainties. | We report the status of RBCK calculations on nucleon structure with quenched and dynamical domain wall fermions. The quenched results for the moments of structure functions 〈 x 〉 q , 〈 x 〉 Δ u − Δ d , and 〈 1 〉 δ q from 1.3 GeV cutoff lattices are complete with non perturbative renormalization (NPR). The dynamical results with two degenerate dynamical quark flavors from 1.7 GeV cutoff lattices are without NPR while the axial charge result is naturally renormalized. | eng_Latn | 26,736 |
THE DISCOVERY OF NUCLEAR COMPRESSION PHENOMENA IN RELATIVISTIC HEAVY-ION COLLISIONS | One of the first papers discussing the occurrence of shock waves in a nuclear medium appeared in 1956 under the title Hydrodynamic theory of multiple production of particle by S. Z. Belen'kij and L. D. Landau. They described the first stage of a nucleus-nucleus collision as a compression of the nuclear substance causing a shock wave travelling over the nuclei. This paper reports it is this outward flow of nuclear matter which became, more than two decades later, one of the most exciting topics of theoretical and experimental nuclear physics. | Using $sup 4$He as an example, it is shown that in the reaction ($pi$$sup -$, nn) the pion rescattering effect plays a decisive role at small momentum transfers, while the effective exchange between all nucleons in the final state plays a major role at large transfers. This leads to the appearance of corresponding two maxima, in agreement with the recently obtained experimental data. | yue_Hant | 26,737 |
Right-handed lepton mixings at the LHC | 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. | 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 | 26,738 |
Measurement of transverse wakefields induced by a misaligned positron bunch in a hollow channel plasma accelerator | Hollow channel plasma wakefield acceleration is a proposed method to provide high acceleration gradients for electrons and positrons alike: a key to future lepton colliders. However, beams which are misaligned from the channel axis induce strong transverse wakefields, deflecting beams and reducing the collider luminosity. This undesirable consequence sets a tight constraint on the alignment accuracy of the beam propagating through the channel. Direct measurements of beam misalignment-induced transverse wakefields are therefore essential for designing mitigation strategies. We present the first quantitative measurements of transverse wakefields in a hollow plasma channel, induced by an off-axis 20 GeV positron bunch, and measured with another 20 GeV lower charge trailing positron probe bunch. The measurements are largely consistent with theory. | 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. | eng_Latn | 26,739 |
Uniruled Symplectic 4-Manifolds | This chapter includes a gentle introduction to the Gromov-Witten invariants, and then explores the relationship between these and McDuff’s results on rational/ruled surfaces, including a complete proof that the latter are the only symplectic 4-manifolds that are uniruled. | 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. | eng_Latn | 26,740 |
Soliton emission at a phase-mismatch boundary in a quadratic nonlinear film waveguide | We report the experimental demonstration of spatial nonlinear beam displacement caused by an interface between periodically modulated and uniform quadratic nonlinearity. We observe intensity- and phase-mismatch-dependent spatial beam displacement at 1548 nm in lithium niobate waveguides. The device has the potential to provide a soliton-emission-based, ultrafast all-optical switch. | 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 | 26,741 |
TWO-DIMENSIONAL NMR STUDY OF ELEDOISIN | The 1 H and 13 C NMR spectra of eledoisin, an antidiuretic hormone, were studied by two-dimensional NMR techniques. All the 1 H and 13 C NMR resonances were unambiguously determined from a combination of the 2D homo- and hetero-nuclear NMR spectra | 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. | yue_Hant | 26,742 |
Hadron Masses in Strong Magnetic Fields | Hadron masses under strong magnetic fields are studied. In the presence of strong magnetic fields exceeding the QCD energy scale $ eB \gg \Lambda^2_{\rm QCD} $, ${\rm SU(3)}_{\rm flavor} \otimes {\rm SU(2)}_{\rm spin}$ symmetry of hadrons is explicitly broken so that the quark components of hadrons differ from those with zero or weak magnetic fields $ eB \lesssim \Lambda^2_{\rm QCD} $. Also, squeezing of hadrons by strong magnetic fields affects the hadron mass spectrum. We develop a quark model which appropriately incorporates these features and analytically calculate various hadron masses including mesons, baryons and those with strangeness. | 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 | 26,743 |
Angular anisotropy of the Kr 3d(3/2,5/2)(-1)5p-g4p(-2)5p resonant Auger decay studied by utilizing the auger resonant Raman effect | The anisotropy of the resonant Auger decay of the photoexcited Kr 3d(3/2,5/2)(-1)5p states has been studied by comparing the new high-resolution experimental results with the multiconfiguration Dir ... | The neutrinoproduction of $\phi$ and $D^+_s$ mesons is studied, using the data obtained with the SKAT bubble chamber at the Serpukhov accelerator. It is found that the $\phi$ production occurs predominantly in the forward hemisphere of the hadronic c.m.s. (at $x_F > 0$, $x_F$ being the Feynman variable), with the mean yield strongly exceeding the expected yield of directly produced $\phi$ mesons and varying from $ 0) > = (0.92\pm0.34) \cdot 10^{-2}$ at $W > $ 2 GeV up to $(1.23\pm0.53) \cdot 10^{-2}$ at $W >$ 2.6 GeV and $(1.44\pm0.69) \cdot 10^{-2}$ at $W >$ 2.9 GeV, $W$ being the invariant mass of the hadronic system. The yield of leading $D^+_s$ mesons carrying more than $z = 0.85$ of the current $c$- quark energy is estimated: at $W > 2.9$ GeV, $ 0.85) > = (6.64\pm1.91) \cdot 10^{-2}$. It is shown, that the shape of the $\phi$ meson differential spectrum on $x_F$ is reproduced by that expected from the $D^+_s \to \phi X$ decays which, however, can account for only the half of the measured $\phi$ yield. | eng_Latn | 26,744 |
Could the dynamics of the Universe be influenced by what is going on inside black holes? | We investigate the potential impact of mass inflation inside black holes on the dynamics of the Universe, considering a recent reformulation of general relativity, proposed in [1], which prevents the vacuum energy from acting as a gravitational source. The interior dynamics of accreting black holes is studied, at the classical level, using the homogeneous approximation and taking charge as a surrogate for angular momentum. We show that, depending on the accreting fluid properties, mass inflation inside black holes could influence the value of the cosmological constant and thus the dynamics of the Universe. A full assessment of the cosmological role played by black holes will require a deeper understanding of the extremely energetic regimes expected inside real astrophysical black holes, including their relation with the physics of the very early Universe, and may eventually lead to an entirely new paradigm for the origin and evolution of the Universe. | 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 | 26,745 |
Productions of Many Atom Entangled States and Their Interferometric Applications | Interferometric precision with N uncorrelated particles is bounded by the standard quantum limit (SQL). We report deterministic generations of entangled atomic states as well as their sensing precisions more than 8dB beyond the SQL. | After making some critical comments about the traditional method of extracting the gluon condensate from lattice QCD data, I present an alternative analysis. The result is more than a factor of five larger than the phenomenological value. Two closely related subjects, the effects of the infrared renormalons on the extraction and the Lepage and Mackenzie improvement on a lattice perturbation series, are also discussed. | eng_Latn | 26,746 |
Integer-Squared Laws for Global Vortices in the Born--Infeld Wave Equations | Abstract A series of quantization identities are established for static vortex solutions governed by the Born–Infeld type actions. These identities are of a universal nature which are indifferent to the details of the models and provide refined descriptions of divergent energetic quantities. | 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 | 26,747 |
Resonant mechanism of axion photoproduction in a magnetized electron gas | It was shown that the contribution of diagrams with electron-positron vacuum excitation in a strong magnetic field B ≫ B 0 = m 2/e = 4.41 × 1013 G in the Compton mechanism of axion production γe → ae at temperatures on the order of the axion mass exceeds the contribution of the “simple” Compton diagram and the contribution of the neutrino production γe → (ν\(\bar \nu \))e to the radiation power by many orders of magnitude. The conclusion is made on the probable axionic nature of the cold hidden mass of the Universe. | 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 | 26,748 |
Lattice results for the QCD phase transition | We discuss recent results for the phase transition in finite-temperature QCD from numerical (Monte Carlo) simulations of the lattice-regularized theory. Emphasis is given to the case of two degenerate light-quark flavors. The order of the transition in this case, which could have cosmological implications, has not yet been established. | Abstract The burning history of a spherical diffusion flame element (Lagrangian flamelet) is modeled under three distinctive burning conditions: a quasi-steady burning process, a quasi-periodic burning mode, and a purely transient burning condition. In the quasi-periodic burning mode, the time scale of the oscillations is shown to affect the chemistry by providing an observed extinction reignition process associated with the unsteady fuel flux into the flame sheet. For the purely transient burning process radiation extinction occurs for certain soot loadings, initial fuel element sizes, and environmental temperatures. | eng_Latn | 26,749 |
Measurement of D^\pm production in deep inelastic ep scattering with the ZEUS detector at HERA | A bstractCharm production in deep inelastic ep scattering was measured with the ZEUS detector using an integrated luminosity of 354 pb−1. Charm quarks were identified by reconstructing D± mesons in the D± → K∓π±π± decay channel. Lifetime information was used to reduce combinatorial background substantially. Differential cross sections were measured in the kinematic region 5 < Q2< 1000 GeV2, 0.02 < y < 0.7, 1.5 < pT (D±) < 15 GeV and |η(D±)| < 1.6, where Q2 is the photon virtuality, y is the inelasticity, and pT (D±) and η(D±) are the transverse momentum and the pseudorapidity of the D± meson, respectively. Next-to-leading-order QCD predictions are compared to the data. The charm contribution, $ F_2^{{c\overline{c}}} $, to the proton structure-function F2 was extracted. | Abstract A layer of random defects in the simple cubic Ising model with nearest neighbor ferromagnetic interactions of strength J is considered. Using the real space renormalization group method we calculate defect free energy in the whole temperature range. Specifically, we analyze: the layer of diluted defects, the layer of spin-glass type defects, and the layer of mixed defects. The free energy is strongly dependent on the value of couplings between the defect and the bulk. | eng_Latn | 26,750 |
Production of ρ0 and f in π−p interactions at 16 GeV/c and separation into fragmentation and central components | Abstract The production of ρ0(770) and f(1270) is studied in π−p interactions at 16 GeV/c. By comparison with inclusive K∗0 production in the reaction K − p → K ∗0 + anything, and with inclusive ρ0 production in the reaction pp → ρ0 + anything, it is found that the data can be interpreted in terms of two production processes: the central production of resonances and the fragmentation of the beam particle. For the π−p reaction, the inclusive ρ0 beam fragmentation cross section is 3.1 ± 0.3 mb while that for central production is 1.6 ± 0.5 mb. The ρ0 central production cross section is consistent with increasing with energy as ln s behaviour. The ratio of ρ0 to π− inclusive cross sections (excluding the leading π−) is ∼0.2, independent of energy. The ρ0 to π− ratio increases as a function of pT to a constant value of ∼ 1 2 above 1 GeV/c. The ρ (charged and neutral) and f decays account for (25 ± 4)% and (1.4 ± 0.3)%, respectively, of all pions produced. | In this note, we determine the ground state energy of the translation invariant Pauli-Fierz model to subleading order $O(\alpha^3)$ with respect to powers of the finestructure constant $\alpha$, and prove rigorous error bounds of order $O(\alpha^{4})$. A main objective of our argument is its brevity. | eng_Latn | 26,751 |
Jet Production in Association with Vector Bosons or Top Quarks | The LHC experiments ATLAS and CMS have measured V+jets and ttbar+jets final states over a large energy range in data collected between 2010 and 2012 at sqrt(s) = 7 TeV and sqrt(s) = 8 TeV. The results have been compared to pQCD calculations at NLO and have been used to validate novel Monte Carlo techniques. | Abstract A series of quantization identities are established for static vortex solutions governed by the Born–Infeld type actions. These identities are of a universal nature which are indifferent to the details of the models and provide refined descriptions of divergent energetic quantities. | eng_Latn | 26,752 |
Some maximal balls in quasi-Fuchsian once punctured torus space ∗ | In this article we exhibit some balls lying in the quasi-Fuchsian space of once punctured tori, which are maximal in the class of balls with the same centers. The centers of our maximal balls lie on the slice determined by the trace equation y = ¯ x. | 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 | 26,753 |
Soliton Models for the Nucleon and Predictions for the Nucleon Spin Structure ∗) | In these lectures the three flavor soliton approach for baryons is reviewed. Effects of flavor symmetry breaking in the baryon wave--functions on axial current matrix elements are discussed. A bosonized chiral quark model is considered to outline the computation of spin dependent nucleon structure functions in the soliton picture. | Abstract In order to study the size distribution of a radioactivity due to radon daughters in the environmental atmosphere, an experimental procedure using filters, ion tubes, diffusion batteries and cascade impactors (CASELLA MK2 and ANDERSEN) is presented. A comparison between the experimental results and a theoretical curve, deduced of the attachment theory of the small radioactive ions on atmospheric particles, is carried out. | eng_Latn | 26,754 |
STRUCTURE FUNCTIONS AND LOW X PHYSICS by | 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. | In this paper, we obtain a $\alpha$-Suzuki fixed point theorem by using $C$ - class function on quasi metric spaces. Also we give an example which supports our main theorem. | yue_Hant | 26,755 |
Effect of potassium and barium on the stability of a carbon-supported ruthenium catalyst for the synthesis of ammonia | Abstract The effect of potassium and barium on the activity and thermal stability of a carbon-based ruthenium catalyst for the synthesis of ammonia has been studied. Kinetic measurements in NH 3 synthesis were carried out in a flow differential reactor operating at standard conditions ( p =6 MPa, T =673 K, X NH 3 =8%, H 2 : N 2 =3 : 1). Overheating of the samples was carried out at 793 K for 24 h. The examinations have been supplemented by XRD and chemisorption studies for the characterization of the ruthenium dispersion as well as by studying the catalysts methanation. It has been found that the barium-promoted catalyst is more active in NH 3 synthesis and more resistant to overheating than the catalyst promoted with potassium. The activity of Ba–Ru/C is much higher than that of a commercial fused-iron catalyst. This is important for industrial practice. | We calculate the threshold T-matrices of kaon-nucleon and antikaon-nucleon scattering to one loop order in SU(3) heavy baryon chiral perturbation theory. To that order the complex-valued isospin-1 $\bar KN$ threshold T-matrix can be successfully predicted from the isospin-0 and 1 $KN$ threshold T-matrices. As expected perturbation theory fails to explain the isospin-0 $\bar KN$ threshold T-matrix which is completely dominated by the nearby subthreshold $\Lambda^*(1405)$-resonance. Cancelations of large terms of second and third chiral order are observed as they seem to be typical for SU(3) baryon chiral perturbation theory calculations. We also give the kaon and eta loop corrections to the $\pi N$ scattering lengths and we investigate $\pi\Lambda$ scattering to one-loop order. The second order s-wave low-energy constants are all of natural size and do not exceed 1 GeV$^{-1}$ in magnitude. | eng_Latn | 26,756 |
Role of the tensor interaction in He isotopes with a tensor-optimized shell model | We studied the role of the tensor interaction in He isotopes systematically on the basis of the tensor-optimized shell model (TOSM). We use a bare nucleon-nucleon interaction AV8${}^{\ensuremath{'}}$ obtained from nucleon-nucleon scattering data. The short-range correlation is treated in the unitary correlation operator method (UCOM). Using the TOSM + UCOM approach, we investigate the role of tensor interaction on each spectrum in He isotopes. It is found that the tensor interaction enhances the $LS$ splitting energy observed in ${}^{5}$He, in which the ${p}_{1/2}$ and ${p}_{3/2}$ orbits play different roles on the tensor correlation. In ${}^{6,7,8}$He, the low-lying states containing extra neutrons in the ${p}_{3/2}$ orbit gain the tensor contribution. On the other hand, the excited states containing extra neutrons in the ${p}_{1/2}$ orbit lose the tensor contribution due to the Pauli-blocking effect with the $2p2h$ states in the ${}^{4}$He core configuration. | Using the Stevens–Tiersten equation for slowly varying thickness modes in doubly rotated quartz plate piezoelectric resonators, we determine optimal electrode shape and size for these resonators. The electrodes obtained are optimal in that they satisfy Bechmann’s number in every direction. | eng_Latn | 26,757 |
Negative parity bands in 100Ru and 150Sm and the interacting boson approximation | Ground-state band members up to Jπ = 10+ in 100Ru and up to 14+ in 150Sm and odd-spin negative parity states up to 15− in both nuclei have been identified from (α, 4n) in-beam γ-ray and conversion electron spectra. The data are interpreted in terms of interacting quadrupole and octupole bosons. | Lack-of-fit testing of a regression model with Berkson measurement error has not been discussed in the literature to date. To fill this void, we propose a class of tests based on minimized integrated square distances between a nonparametric regression function estimator and the parametric model being fitted. We prove asymptotic normality of these test statistics under the null hypothesis and that of the corresponding minimum distance estimators under minimal conditions on the model being fitted. We also prove consistency of the proposed tests against a class of fixed alternatives and obtain their asymptotic power against a class of local alternatives orthogonal to the null hypothesis. These latter results are new even when there is no measurement error. A simulation that is included shows very desirable finite sample behavior of the proposed inference procedures. | eng_Latn | 26,758 |
Acousto-optically Q-switched diode side-pumped Er:YLF laser generating 50-kW peak power in 70-ns pulses | We report on a newly developed Q-switched diode side-pumped Er:YLF solid state laser emitting at 2.81 μm. Efficient short pulse generation is achieved by utilizing the relatively long lifetime of the upper laser level and the inherently linear polarized laser light of the Er:YLF crystal material. By means of an acousto-optic switch, peak powers of 50 kW with corresponding pulse widths of 70 ns and pulse energies of up to 3.5mJ are realized at a repetition rate of 100 Hz. The laser operates efficiently at room temperature and has a compact nature, enabling minimized thermal impact tissue ablation as well as pumping of non-linear crystals for mid-IR generation. | The neutrinoproduction of $\phi$ and $D^+_s$ mesons is studied, using the data obtained with the SKAT bubble chamber at the Serpukhov accelerator. It is found that the $\phi$ production occurs predominantly in the forward hemisphere of the hadronic c.m.s. (at $x_F > 0$, $x_F$ being the Feynman variable), with the mean yield strongly exceeding the expected yield of directly produced $\phi$ mesons and varying from $ 0) > = (0.92\pm0.34) \cdot 10^{-2}$ at $W > $ 2 GeV up to $(1.23\pm0.53) \cdot 10^{-2}$ at $W >$ 2.6 GeV and $(1.44\pm0.69) \cdot 10^{-2}$ at $W >$ 2.9 GeV, $W$ being the invariant mass of the hadronic system. The yield of leading $D^+_s$ mesons carrying more than $z = 0.85$ of the current $c$- quark energy is estimated: at $W > 2.9$ GeV, $ 0.85) > = (6.64\pm1.91) \cdot 10^{-2}$. It is shown, that the shape of the $\phi$ meson differential spectrum on $x_F$ is reproduced by that expected from the $D^+_s \to \phi X$ decays which, however, can account for only the half of the measured $\phi$ yield. | eng_Latn | 26,759 |
Characteristic analysis for the Integrated operational amplifiers with negative feedack configuration | Characteristic analysis for the integrated operational amplifiers with negative feedback configuration by means of block diagram topology is described. A set of satisfactory approximate expressions for engineering design are achieved. We also discuss the influence on the negative feedback amplifier properties due to perameters of nonideal OP Amp and the circuit components and compare the analytical results with those of the ideal Op Amp. Key words:integrated operational amplifier; negative feedback; analysis method of block diagram topology | The ratio of the axial to vector neutron decay constants is determined via QCD sum rules. The advantageous use of the arbitrariness in the definition of the nucleon operator leads to a result which is unambiguous. The only input parameter is the value of the chiral symmetry breaking vacuum quark condensate.\(\langle \bar \Psi \Psi \rangle ^{{1 \mathord{\left/ {\vphantom {1 3}} \right. \kern-\nulldelimiterspace} 3}} = - 250 MeV\) the output isgA/gV=1.22. | eng_Latn | 26,760 |
Analytical Heavy Quark Expansion in the ’ t Hooft Model | We present a number of exact relations for the heavy quark limit and develop an analytical 1/m{sub Q} expansion for heavy mesons in the 't Hooft model. Among the new results are the relation 3{mu}{sub {pi}}{sup 2}={bar {Lambda}}{sup 2}-m{sub sp}{sup 2}+{beta}{sup 2},1/m{sub Q} corrections to the decay constants, to the kinetic expectation values, and 1/m{sub Q}{sup 2} nonperturbative corrections to the B{yields}D amplitude at zero recoil. The properties of the IW functions are addressed and the small velocity sum rules are verified. | A generalized canonical form of multi-time dynamical theories is proposed. This form is a starting point for a modified canonical quantization procedure of theories based on a quantum version of the action principle. As an example, the Fokker theory of a direct electromagnetic interaction of charges is considered. | eng_Latn | 26,761 |
WI) Further Comments about B-Physics in pp Interactions* | We summarize discussions concerning the study of B-physics at the SSC. Different approaches are considered. The first one corresponds to the collider experiments detecting charged particles with pseudo-rapidity of {vert_bar}{eta}{vert_bar}{le} 2.4 whereas the second method considers the detection of B-mesons in the forward/backward directions. The utilization of external or gas-jet targets are also briefly discussed. | 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 | 26,762 |
Some multivariate singular unified skew-normal distributions and their application | AbstractWe introduce here the truncated version of the unified skew-normal (SUN) distributions. By considering a special truncations for both univariate and multivariate cases, we derive the joint distribution of consecutive order statistics X(r, ..., r + k) = (X(r), ..., X(r + K))T from an exchangeable n-dimensional normal random vector X. Further we show that the conditional distributions of X(r + j, ..., r + k) given X(r, ..., r + j − 1), X(r, ..., r + k) given (X(r) > t) and X(r, ..., r + k) given (X(r + k) < t) are special types of singular SUN distributions. We use these results to determine some measures in the reliability theory such as the mean past life (MPL) function and mean residual life (MRL) function. | 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 | 26,763 |
Coherent DQPSK detectors based on mean square error carrier phase estimation and decision feedback | Chalmers University of TechnologyDepartment of Information TheoryS-412 96 Gothenburg, Swedenphone +46 31 772 17 51 or +46 70 565 48 20fax +46 31 772 17 48e-mail [email protected]. Novel coherent detectors for DQPSKand π/4-DQPSK on fading channels are pre-sented. The phase reference for the decisiondevice is derived by mean square error estimationof the fading process. A finite impulse responsefilter is used for this purpose. The decision deviceis a traditional coherent detector. Both 1 and 2stage detectors are considered. The proposeddetectors show significantly better performancein fast fading compared to a differential detector. | Bottom-up holographic models of QCD, inspired by the anti-de Sitter space/conformal field theory correspondence, have shown a remarkable degree of phenomenological success. However, they rely on a number of bold assumptions. We investigate the reliability of one of the key assumptions, which involves matching the parameters of these models to QCD at high 4D momentum q{sup 2} and renormalization scale {mu}{sup 2}. We show that this leads to phenomenological and theoretical inconsistencies for scale-dependent quantities such as . | eng_Latn | 26,764 |
Hydrogen sulfide: a novel gaseous signaling molecule and intracellular Ca2+regulator in rat parotid acinar cells | In addition to nitric oxide (NO), hydrogen sulfide (H2S) is recognized as a crucial gaseous messenger that exerts many biological actions in various tissues. An attempt was made to assess the roles and underlying mechanisms of both gases in isolated rat parotid acinar cells. Ductal cells and some acinar cells were found to express NO and H2S synthases. Cevimeline, a muscarinic receptor agonist upregulated endothelial NO synthase in parotid tissue. NO and H2S donors increased the intracellular Ca2+ concentration ([Ca2+]i). This was not affected by inhibitors of phospholipase C and inositol 1,4,5-trisphosphate receptors, but was decreased by blockers of ryanodine receptors (RyRs), soluble guanylyl cyclase, and protein kinase G. The H2S donor evoked NO production, which was decreased by blockade of NO synthases or phosphoinositide 3-kinase or by hypotaurine, an H2S scavenger. The H2S donor-induced [Ca2+]i increase was diminished by a NO scavenger or the NO synthases blocker. These results suggest that NO and... | This paper addresses the question of observability of neutral Higgs bosons through the leptonic decay in a two Higgs doublet model (2HDM). Both scalar and pseudoscalar Higgs bosons ($H,~A$) are considered. The model is set to type IV to enhance the leptonic decay. In such a scenario, a signal production process like $e^+e^- \to A^0H^0 \to \tau\tau \mu\mu$ or $\mu\mu\tau\tau$ would provide a clear signal on top of the background in a di-muon invariant mass distribution far from the $Z$ boson pole mass. The analysis is based on a $\tau$-id algorithm which preselects events if they have two $\tau$ jets by requiring a hadronic $\tau$ decay. Several benchmark points are defined for the search, requiring a linear collider operating at $\sqrt{s} =$ 0.5 and 1 TeV. It is shown that the signal can be observed on top of the background in all benchmark points at an integrated luminosity of 1000 $fb^{-1}$. | eng_Latn | 26,765 |
Kardar-Parisi-Zhang universality from soft gauge modes | The emergence of superdiffusive spin dynamics in integrable classical and quantum magnets is well established by now, but there is no generally valid theoretical explanation for this phenomenon. A fundamental difficulty is that the hydrodynamic fluctuations of conserved quasiparticle modes are purely diffusive. We propose a "hydrodynamic Higgs mechanism" in isotropic integrable magnets, which generates soft gauge modes that are decoupled from the quasiparticle sector. We show that the coarse-grained time evolution of these modes lies in the Kardar-Parisi-Zhang universality class of dynamics. | Using inelastic scattering of polarized neutrons near a finite Bragg reflection, the dynamics of longitudinal \ensuremath{\delta}S(q)\ensuremath{\parallel}q and transverse \ensuremath{\delta}S(q)\ensuremath{\perp}q spin fluctuations have been measured. The relaxation rates ${\mathrm{\ensuremath{\Gamma}}}_{\mathrm{\ensuremath{\alpha}}}$ follow rather precisely the dipolar dynamic-scaling function calculated recently by mode-coupling theory based on the Lorentzian approximation. The predicted longitudinal line shape near ${\mathit{T}}_{\mathit{C}}$ disagrees with our data. | eng_Latn | 26,766 |
Nucleon resonance decay by the K0Σ+ channel | With the combined setup of the Crystal Barrel and TAPS photonspectrometers at ELSA in Bonn we have studied photonuclear reactions on protons and deuterons. From the series of experiments on single and multiple neutral meson emission we concentrate here on the hyperon production off protons and deuterons, and in particular on the K 0Σ+ decay channel. The reaction is characterized by the final state of 6 photons and a forward emitted proton. We report on the first results from this channel. | 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 | 26,767 |
The effect of host medium on the half-life of 7Be | Abstract We discuss recent results of E.B. Norman et al. [Phys. Lett. B 519 (2001) 15] in relation to our earlier work [A. Ray et al., Phys. Lett. B 455 (1999) 69] and point out that the apparent disagreement between the two sets of experimental results is most likely due to the choice of different reference samples with which the comparisons have been done. In addition, the irradiation by heavy ion beam might also damage the lattice structure of the medium and such effect was not included in our calculations. We think that our earlier conclusion regarding the downward revision of predicted 8B solar neutrino flux by ≈2% should stand. | Angular distributions for the reaction /sup 9/Be(/sup 3/He,d) have been measured for all levels below 6.8 MeV in /sup 10/B. Data confirm that states at 6.13 and 6.57 MeV, previously assigned J/sup ..pi../=3/sup -/ and (4)/sup -/, respectively, have the same parity. Their strengths are consistent with their being the 3/sup -/ and 4/sup -/ states expected in this region of excitation. | eng_Latn | 26,768 |
Rotational Behaviour of Comet Nuclei | Numerical experiments of the rotational behaviour of comet nuclei have been performed, including the Sun and Jupiter’s disturbing torques in the models. In a stable configuration, the solar torque induces great librations that remain unchanged along the orbit. A close approach with Jupiter can result in great changes on the rotational pattern because of the motion sensitivity to initial conditions. The unstable configuration is characterized by great librations of the nutation angle, and the existence of a possibly large chaotic zone in the phase space. | 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. | kor_Hang | 26,769 |
Neutron spin structure results from JLab Hall A | My presentation will focus on some of the latest results of the neutron spin physics program at Jefferson Laboratory in Hall A using a polarized 3He target. This program includes several completed experiments in which the spin structure functions of 3He were measured. The covered kinematic regions were these measurements were performed include the low Q2 resonance and inelastic regions and the high Q2 deep inelastic region. These experiments offer a ground for testing our understanding of the strong regime of quantum chromodynamics (QCD) through the determination of the neutron spin‐dependent structure functions and their moments. | It is shown that the inclusion of pion, nucleon, and delta mass differences, and eta-..pi.. mixing, in a coupled-channels treatment of the deuteron leads to small components of the wave function with isospin -1 and even isospin -2. | eng_Latn | 26,770 |
Structural Control of Cubic and Hexagonal GaN by Changing the Electric Bias during ECR‐MBE Growth | Controlling the crystal structure of GaN as either cubic (c-) or hexagonal (h-) GaN by changing the electric bias during growth was studied. After growth, we used transmission electron microscopy (TEM) and X-ray diffraction to determine the microstructure of c-GaN and h-GaN. Although c-GaN was confirmed, the interface at h-GaN/c-GaN was not clear. To increase the transition rates of crystal structure at the interface, we added hydrogen as a hydrogen-nitrogen mixed gas plasma while changing the electric bias. When we introduced hydrogen for 20 s while simultaneously changing the electric bias from 20 to 0 V, the crystal structure of GaN changed abruptly from cubic to hexagonal. TEM observations showed that the interface contained a thin layer with a high density of stacking faults, indicating that addition of hydrogen clearly assisted the change of crystal structure by forming stacking faults. | 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 | 26,771 |
Construction of the Covariantly Quantized Heterotic Superstring | We give a detailed discussion of the construction of the Batalin-Vilkovisky BRST charge for the heterotic superstring. In particular, we completely solve the higher-ghost sector using a recursion relation. The gauge choice ▽+θ = 0, which we previously proposed for the superparticle, leads to a free quantum action. | 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 | 26,772 |
High-resolution studies of spin–isospin modes and neutrino–nucleus reactions in supernovae | Abstract Some aspects of the importance of neutrino-induced reactions on nuclei within supernova physics are discussed. It is argued that important constraints on the experimentally unknown cross sections can be obtained from experimental studies of the nuclear response in selected cases. Examples are neutral-current-induced reactions on f p -shell nuclei extracted from high-resolution inelastic electron scattering data providing the M 1 strength distributions and the Gamow–Teller strength in the exotic heavy, odd–odd nuclei 138 La and 180 Ta deduced from the ( 3 He, t ) charge-exchange reaction at zero degree. | We calculate the mass of thec\(\bar s\)P state recently observed by the ARGUS group and find that we get good predictions for a variety of potential models in the case of nonrelativistic kinematics. We also calculate the masses of other quark-antiquark states with the same models, using both nonrelativistic kinematics and a simple prescription for incorporating relativistic kinematics. It turns out that in the case of nonrelativistic kinematics, the calculated mass of the 1P state ofc\(\bar s\) is relatively insensitive to the form of the potential, while the masses of some other states depend to a greater degree on the potential. When we use relativistic kinematics, the spread in the calculated values becomes larger. We conclude that in the case of nonrelativistic kinematics, the predicted mass of the 1P state ofc\(\bar s\) is less model dependent than those of some other states, but that measurement of other states can give us more information about the quark-antiquark potential. | eng_Latn | 26,773 |
Carrier lifetime control in III-V multiple quantum wells | We report carrier lifetime reduction in GaInAs/InP multiple quantum wells from 3Ons to 95ps using mesas with ion implantation of the sidewalls.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only. | Bottom-up holographic models of QCD, inspired by the anti-de Sitter space/conformal field theory correspondence, have shown a remarkable degree of phenomenological success. However, they rely on a number of bold assumptions. We investigate the reliability of one of the key assumptions, which involves matching the parameters of these models to QCD at high 4D momentum q{sup 2} and renormalization scale {mu}{sup 2}. We show that this leads to phenomenological and theoretical inconsistencies for scale-dependent quantities such as . | eng_Latn | 26,774 |
Mean-field repulsion of colliding nuclear matter at relativistic energies | The authors study the energy behaviour of two penetrating interacting nuclear matter systems in a relativistic quantum field theory proposed by J.D. Walecka (1974). They show that, compared with non-interacting systems, the relative flow velocity is significantly reduced due to the repulsive omega -meson field and discuss an effective potential between the matter systems. | It was recently suggested that the rise in the photopion cross sections above 500 Mev may be interpreted as being due to another resonance in the pion- nucleon system. Since the pi /sup +/ cross section is the larger, the resonance must presumably be in a T = 1/2 state. From observation of the angular distributions, it is also possible to determine the probable angular momentum and parity of such a state. (W.D.M.) | eng_Latn | 26,775 |
Experimental bounds on sterile neutrino mixing angles | We derive bounds on the mixing between the left-chiral ("active") and the right-chiral ("sterile") neutrinos, provided from the combination of neutrino oscillation data and direct experimental searches for sterile neutrinos. We demonstrate that the mixing of sterile neutrinos with any flavour can be significantly suppressed, provided that the angle theta_13 is non-zero. This means that the lower bounds on sterile neutrino lifetime, coming from the negative results of direct experimental searches can be relaxed (by as much as the order of magnitude at some masses). We also demonstrate that the results of the negative searches of sterile neutrinos with PS191 and CHARM experiments are not applicable directly to the see-saw models. The reinterpretation of these results provides up to the order of magnitude stronger bounds on sterile neutrino lifetime than previously discussed in the literature. We discuss the implications of our results for the Neutrino Minimal Standard Model (the NuMSM). | Interferometric precision with N uncorrelated particles is bounded by the standard quantum limit (SQL). We report deterministic generations of entangled atomic states as well as their sensing precisions more than 8dB beyond the SQL. | eng_Latn | 26,776 |
Study of e~+e~-→τ~+μ~- in the LH Model | The cross section for the process e~+e~-→τ~+μ~- is enhanced significantly in the littlest Higgs model(LH model),by the one-loop contribution which involves the flavor change coupling between the mirror lepton and the standard model(SM) lepton from the vertex angle of τ+μ-Z(γ).The process e~+e~-→τ~+μ~- within the LH model is investigated.Reasonable numerical result of σ is obtained by using High Energy Physics and Loop Tools in Mathematica 7.0.It can be observed at future e+e-linear colliders,which is in favor of testing the LH model. | We give some hypotheses under which it, is easy to compute the growth function of free products and HNN extensions. | eng_Latn | 26,777 |
MECHANISMS OF ELIMINATION REACTIONS. 33. CARBON ISOTOPE EFFECTS IN E2 REACTIONS OF (2-PHENYLETHYL-2-14C)TRIMETHYLAMMONIUM ION. THE ROLE OF TUNNELING | Carbon isotope effects have been determined for the reactions of (2-phenylethyl-2-/sup 14/C)trimethylammonium ion with hydroxide ion in 10, 25, 40, and 60% Me/sub 2/SO-water and with ethoxide ion in dry ethanol. Comparison of these values with earlier results on /sup 13/C isotope effects shows that the relation between the /sup 14/C and /sup 13/C effects is close to that predicted from theory. The magnitudes of the isotope effects suggest significant contributions from tunneling, and this suggestion is supported by temperature-dependence studies that give ..delta..E/sub a/ values too large and A/sub a(12)//A/sub a(14)/ values too small to account for without tunneling. Temperature dependences calculated from the Bell theory of tunneling can be fitted to the experimental data. The results indicate that the semiclassical (without tunneling) carbon isotope effects are small or even inverse and that tunnel corrections make major contributions to the observed isotope effects. | We calculate the threshold T-matrices of kaon-nucleon and antikaon-nucleon scattering to one loop order in SU(3) heavy baryon chiral perturbation theory. To that order the complex-valued isospin-1 $\bar KN$ threshold T-matrix can be successfully predicted from the isospin-0 and 1 $KN$ threshold T-matrices. As expected perturbation theory fails to explain the isospin-0 $\bar KN$ threshold T-matrix which is completely dominated by the nearby subthreshold $\Lambda^*(1405)$-resonance. Cancelations of large terms of second and third chiral order are observed as they seem to be typical for SU(3) baryon chiral perturbation theory calculations. We also give the kaon and eta loop corrections to the $\pi N$ scattering lengths and we investigate $\pi\Lambda$ scattering to one-loop order. The second order s-wave low-energy constants are all of natural size and do not exceed 1 GeV$^{-1}$ in magnitude. | yue_Hant | 26,778 |
Parallel loop cluster quantum Monte Carlo simulation of quantum magnets based on global union-find graph algorithm | Abstract A large-scale parallel loop cluster quantum Monte Carlo simulation is presented. On 24,576 nodes of the K computer, one loop cluster Monte Carlo update of the world-line configuration of the S = 1 ∕ 2 antiferromagnetic Heisenberg chain with 2 . 6 × 1 0 6 spins at inverse temperature 3 . 1 × 1 0 5 is executed in about 8.62 s, in which global union-find cluster identification on a graph of about 1.1 trillion vertices and edges is performed. By combining the nonlocal global updates and the large-scale parallelization, we have virtually achieved about 1 0 13 -fold speed-up from the conventional local update Monte Carlo simulation performed on a single core. We have estimated successfully the antiferromagnetic correlation length and the magnitude of the first excitation gap of the S = 4 antiferromagnetic Heisenberg chain for the first time as ξ = 1 . 040 ( 7 ) × 1 0 4 and Δ = 7 . 99 ( 5 ) × 1 0 − 4 , respectively. | 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 | 26,779 |
Phonon coherence in isotopic silicon superlattices | Recent experimental and theoretical investigations have confirmed that a reduction in thermal conductivity of silicon is achieved by isotopic silicon superlattices. In the present study, non-equilibrium molecular dynamics simulations are performed to identify the isotope doping and isotope layer ordering with minimum thermal conductivity. Furthermore, the impact of isotopic intermixing at the superlattice interfaces on phonon transport is investigated. Our results reveal that the coherence of phonons in isotopic Si superlattices is prevented if interfacial mixing of isotopes is considered. | 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. | eng_Latn | 26,780 |
Measurement of the Top-Antitop Production Cross Section at sqrt(s) = 1.96 TeV in the Combined Lepton+Track and e+mu Channel Using 370 pb^-1 of D0 Data | A measurement of the ttbar production cross section at sqrt(s) = 1.96 TeV in the dilepton final states using a lepton+track selection and secondary vertex b-tagging is presented. One of the two leptons from the decay of the ttbar pair is allowed to be identified only as an isolated track to improve the selection efficiency. The result is combined with a measurement in the ttbar->e+mu final state. The measurements are based on 370 pb^-1 of data collected with the D0 experiment at the Tevatron collider. The preliminary cross section obtained in the combined lepton+track and e+mu channel is: sigma_{ttbar} = 8.6 +1.9 -1.7 (stat) +/- 1.1 (syst) +/- 0.6 (lumi) pb. | 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 | 26,781 |
Nucleon nucleon scattering in a chiral constituent quark model | We study the nucleon-nucleon interaction in a chiral constituent quark model by using the resonating group method, convenient for treating the interaction between composite particles. The calculated phase shifts for the ${}^{3}{S}_{1}$ and ${}^{1}{S}_{0}$ channels show the presence of a strong repulsive core due to the combined effect of the quark interchange and the spin-flavor structure of the effective quark-quark interaction. Such a symmetry structure stems from the pseudoscalar meson exchange between the quarks and is a consequence of the spontaneous breaking of the chiral symmetry. We perform single and coupled channel calculations and show the role of coupling of the $\ensuremath{\Delta}\ensuremath{\Delta}$ and hidden color $\mathrm{CC}$ channels on the behavior of the phase shifts. | 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 | 26,782 |
Low-energy neutral atom signatures of magnetopause motion in response to southwardBz | [1] We report an event observed by the Low-Energy Neutral Atom (LENA) imager on 18 April 2001, in which enhanced neutral atom emission was observed coming from the direction of the Sun and from the general direction of the subsolar magnetopause. The enhanced neutral atom emission is shown to be primarily a result of increased solar wind charge exchange with the Earth's hydrogen exosphere, that is, enhanced neutral solar wind formation, occurring in conjunction with a southward turning of the interplanetary magnetic field (IMF) which moves the magnetopause closer to the Earth. It is shown that the neutral atom flux under compressed magnetopause conditions is extremely sensitive to changes in the IMF north-south component. | 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 | 26,783 |
1 Neutrino Physics: Theory and Phenomenology | Various issues in neutrino phenomenology are reviewed, including: the possibility of large mixing angles in various models for neutrino masses, difficulties for degenerate neutrinos as candidates for hot dark matter, strategies for discriminating between different oscillation interpretations of the atmospheric and solar neutrino anomalies, the programme of work for long-baseline neutrino experiments, and the possible future option of a muon storage ring as a neutrino factory. | A Thesis Submitted to the Department of Physics,Kwame Nkrumah University of Science and Technology in partial fulfillment of the requirements for the degree of Master of Philosophy, 2015 | kor_Hang | 26,784 |
Taming the Pion Cloud of the Nucleon | We present a light-front determination of the pionic contribution to the nucleon self-energy, Σ(π), to second order in pion-baryon coupling constants that allows the pion-nucleon vertex function to be treated in a model-independent manner constrained by experiment. The pion mass μ dependence of Σ(π) is consistent with chiral perturbation theory results for small values of μ and is also linearly dependent on μ for larger values, in accord with the results of lattice QCD calculations. The derivative of Σ(π) with respect to μ(2) yields the dominant contribution to the pion content, which is consistent with the d[over ¯]-u[over ¯] difference observed experimentally in the violation of the Gottfried sum rule. | A year after a tsunami triggered meltdown at a Japanese nuclear plant, New Scientist examines the knock-on effects | eng_Latn | 26,785 |
Three-body Effect on ^1S0 Proton and Neutron Superfluidity in Neutron stars | The proton and neutron 1S0 pairing gaps in 13-stable neutron star matter have been studied by using the isospin dependent Brueckner-Hartree-Fock approach and the BCS theory. We have concentrated on investigating and discussing the effect of three-body force. In Fig.1 is plotted the predicted neutron energy gap in the ^1S0 channel as a function of the total baryon density pB. The solid curve is obtained using the AVis interaction plus the three-body force. The dash curve is calculated by adopting the pure AVis two-body potential It isseen that the three-body force effect is quiet small, i.e., quasr negligible at relatively low density and a plight suppression as increasing density. In Fig.2 is reported the proton ^1S0 energy gap in β-stable matter. The solid curve is predicted by using the AVis plus the three-body force, the dash one by using purely the AV18 two-body force. | 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 | 26,786 |
Simulations of Muon Flux in Slanic Salt Mine | Geant4 simulation package was used to simulate muon fluxes at different locations, the floor of UNIREA mine and two levels of CANTACUZINO mine, of Slanic Prahova site in Romania. This site is specially important since it is one of the seven sites in Europe that are under consideration of housing large detector components of Large Apparatus studying Grand Unification and Neutrino Astrophysics (LAGUNA) project. Simulations were performed for vertical muons and for muons with a zenith angle . Primary muon flux and energies at ground level were obtained from previous measurements. Results of the simulations are in general agreement with previous simulations made using MUSIC simulation program and with the measurements made using a mobile detector. | Abstract The evolution of the state vector of a system composed of a cascade three-level atom and a single-mode field with arbitrary detuning and initial condition has been obtained. The quantum fluctuations of the field are presented. The contribution of single- and two-photon transitions to the squeezing of the field is discussed. The dependence of the squeezing on initial intensities of the field and detuning are given. | eng_Latn | 26,787 |
Triple ionization of lithium-like ions by photon impact | Abstract Within the framework of sudden approximation, the non-relativistic cross sections for the triple ionization of Li-like ions caused by absorption and Compton scattering of high-energy photons are calculated. The ratios of the triple-to-single and triple-to-double ionization cross sections are obtained. For neutral lithium atom, our predictions for σ 3 + / σ + and σ 3 + / σ 2 + are compared both with available experimental and theoretical results. | 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 | 26,788 |
Quasar absorption lines and sites of absorbing media | A method for the determination of distances of quasars and sites of absorbing media is presented. It is illustrated by application to 3C 191 and PKS 0237-23. The results are compared with those obtained from the traditional Hubble Law. | Bottom-up holographic models of QCD, inspired by the anti-de Sitter space/conformal field theory correspondence, have shown a remarkable degree of phenomenological success. However, they rely on a number of bold assumptions. We investigate the reliability of one of the key assumptions, which involves matching the parameters of these models to QCD at high 4D momentum q{sup 2} and renormalization scale {mu}{sup 2}. We show that this leads to phenomenological and theoretical inconsistencies for scale-dependent quantities such as . | eng_Latn | 26,789 |
B Physics in the Next Millennium | As we approach the turn of the century, the Standard Model is still consistent with all our experimental observations and the path to a more complete picture of the fundamental constituents and their interactions has yet to be clearly identified. Beauty flavored hadrons have provided crucial experimental information on several fundamental parameters of the Standard Model and may lead to one of the most challenging test of its validity and provide some clues on the path towards a more complete theory. Several experiments will try to explore this rich phenomenology in the next few years. Their physics goals and discovery potential will be compared. | Note: Univ wisconsin madison,dept phys,stoughton,wi 53589. montana state univ,dept phys,bozeman,mt 59717. Kelly, mk, univ wisconsin madison,ctr synchrotron radiat,stoughton,wi 53589.ISI Document Delivery No.: J2593Part 2 Reference LSE-ARTICLE-1987-009 Record created on 2006-10-03, modified on 2017-05-12 | eng_Latn | 26,790 |
Strong interactions and gauge-string duality | 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). | Abstract In this paper, we investigate the time-dependent Ginzburg–Landau (TDGL) equations coming from the superfluid atomic Fermi gases near the Feshbach resonance from the fermion–boson model. By the method of a priori estimates, we get the existence of global attractors in the case of BCS–BEC crossover. | eng_Latn | 26,791 |
Introduction to Electron-Molecule Collisions | The purpose of this introductory chapter is twofold. First, readers of this book are not necessarily specialists in this particular field. Therefore, the editors thought that it would be appropriate to include an introductory chapter which is easily understood. Sophisticated techniques will not be used in this chapter. Only elementary quantum mechanics and basic mathematics will be required to understand this chapter. The theoretical side will be emphasized in this chapter since it is outside my ability to discuss experimental details. | Some discrepancies have been reported between observed and simulated muon content of extensive air showers: the number of observed muons exceeded the expectations in HiRes-MIA, Yakutsk and Pierre Auger Observatory data. Here, we analyze the data of the Moscow State University Extensive Air Shower (EAS-MSU) array on E_mu>~10 GeV muons in showers caused by ~(10^17-10^18) eV primary particles and demonstrate that they agree with simulations (QGSJET-II-04 hadronic interaction model) once the primary composition inferred from the surface-detector data is assumed. | kor_Hang | 26,792 |
The Φ0 → γZ decay in the Littlest Higgs Model | The existence of new particles with masses of the order of TeV's is a characteristic of several extended models. We study a heavy scalar particle decaying into γZ final states at the one-loop level in the Littlest Higgs Model. This process is analyzed in the context of the recent results reported by ATLAS and CMS Collaborations, concerning the observation of a resonance around 750 GeV. We analyze our results in a scenario where the energy scale f ranges from 2 TeV to 5 TeV. We found that the branching ratio for the Φ0 → γZ decay is of the order of 10-7, which mainly depends on a single parameter. | Let q be a positive integer, and L(s, χ ) the Dirichlet L -function corresponding to a Dirichlet character χ mod q . We put where χ runs over all Dirichlet characters mod q except for the principal character χ 0 . | eng_Latn | 26,793 |
Anharmonic effects on phonons in solid krypton | Abstract The wave number dependence of the anharmonic phonon widths and shifts as well as the quasiharmonic dispersion curves has been calculated for solid krypton. The results are compared with experiments by Daniels. The agreement is reasonable and it is seen that the anharmonic shifts contribute significantly to the dispersion curves. | 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 | 26,794 |
Nonlinear interaction of large-amplitude unidirectional waves in shallow water | Nonlinear interaction of long unidirectional waves is studied numerically in the frame- work of nonlinear shallow water theory in a basin of constant depth. The interaction of two initially separated unidirectional waves occurs only when the waves (transformed into the shock waves) overtake each other. It is demonstrated that the interaction of two large-amplitude wave crests results in the formation of one shock wave of triangular shape, which is qualitatively similar to the outcome of the nonlinear interaction of two weak-amplitude waves. The formation of shock waves from initially negative disturbances (wave troughs) is accompanied by the generation of reflected waves of negative polarity. These waves additionally influence the process of interaction. The interaction of waves of opposite polarities is possible only when the leading wave is negative. | 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 | 26,795 |
Pulsed‐nozzle Fourier‐transform microwave investigation of the large‐amplitude motions in HBr–CO2 | Microwave spectra of H79Br–CO2 and H81Br–CO2 and their D and 18O isotopomers have been measured using a pulsed‐nozzle Fourier‐transform microwave spectrometer. The spectra are consistent with a T‐shaped Br–CO2 geometry, as concluded previously by Zeng et al. [Y. P. Zeng, S. W. Sharpe, S. K. Shin, C. Wittig, and R. A. Beaudet, J. Chem. Phys. 97, 5392 (1992)] from an investigation of the rotationally resolved infrared spectrum of the asymmetric C=O stretching vibration of the complex. Only b‐type Ka=1←0 transitions are observed, with the symmetry‐allowed a‐type ΔKa=0 transitions being too weak to be detected. The absence of a strong a‐type spectrum implies that the HBr axis is nearly parallel to the b‐inertial axis of the complex, which itself is parallel to the C∞ axis of the CO2. The Ka=1←0 energy level spacing is approximately 1.2 GHz larger than that predicted from the infrared rotational constants due to an additional contribution to the splitting arising from the hindered‐rotation tunneling of the HBr... | 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. | eng_Latn | 26,796 |
Tunnel ionization of highly excited atoms in a noncoherent laser radiation field | A theory is developed of the ionization of highly excited atomic states by a low-frequency field of noncoherent laser radiation with a large number of modes. Analytic formulas are obtained for the probability of the tunnel ionization in such a field. An analysis is made of the case of the hydrogen atom when the parabolic quantum numbers are sufficiently good in the low-frequency limit, as well as of the case of highly excited states of complex atoms when these states are characterized by a definite orbital momentum and parity. It is concluded that the statistical factor representing the ratio of the probability in a stochastic field to the probability in a monochromatic field decreases, compared with the case of a short-range potential, if the ''Coulomb tail'' is included. It is shown that at a given field intensity the statistical factor decreases on increase in the principal quantum number of the state being ionized. | 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 | 26,797 |
An introduction to the polaron and bipolaron theoretical concepts | A simple model for the autolocalization of a free charged particle is presented. The polarization well in the model is deep enough for only one localized level. In dielectric materials with a sufficiently large dielectric constant, two charged identical particles can be localized in one polarization potential well, forming a bipolaron. Although several localized levels can be found in more realistic self-consistent models of this type, the more realistic theories require a high level of knowledge of mathematics. Hence, the proposed model can serve as an introduction to the ideas and concepts of autolocalized states. | 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 | 26,798 |
Ultrarelativistic nucleus-nucleus collisions and the quark gluon plasma | We present an overview of selected aspects of ultrarelativistic nucleus-nucleus collisions, a research program devoted to the study of strongly interacting matter at high energy densities and in particular to the characterization of the quark-gluon plasma (QGP). The basic features of the phase diagram of nuclear matter, as currently understood theoretically, are discussed. The experimental program, carried out over a broad energy domain at various accelerators, is briefly reviewed, with an emphasis on the global characterization of nucleus-nucleus collisions. Two particular aspects are treated in more detail: i) the application of statistical models to a phenomenological description of particle production and the information it provides on the phase diagram; ii) the production of hadrons carrying charm quarks as messengers from the QGP phase. | A bibliography containing 109 references is presented on the non- destructive analysis of irradiated and unirradiated reactor fuel assemblies. A description of the theory of each method, the equipment utilized, and estimates of the precision obtainable are cortained. Problems presented by variations in enrichment, alloying, cladding, geometrical arrangement, etc., are discussed. (C.J.G.) | eng_Latn | 26,799 |
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