120103449
Determination of average kinetic energy (μ2π) of a heavy quark inside a heavy vector meson using a relativistic method
The average kinetic energy of a heavy quark inside a heavy vector meson was computed using a relativistic Salpeter method. It was found through computation that significant relativistic corrections result in different values of μ2π for pseudoscalar and vector mesons, and μ2π ≈ 0.41 ± 0.07(B*0, B*±), 0.31 ± 0.06(D*0, D*±), 0.48 ± 0.09(B*s), 0.36 ± 0.07(D*s), 0.96 ± 0.17(B*c), 0.62 ± 0.11(J/Ψ) GeV2 for vector mesons.
123969406
Semileptonic Production of Scalar and Tensor p-Wave Charmed Mesons
With the same constituents of quark and antiquark, the p-wave state has a higher mass than the corresponding s-wave state, but the relativistic corrections are much larger in the processes of which p-wave mesons are involved. Considering this, the relativistic Bethe?Salpeter method is applied to estimate the branching fractions of semileptonic decays B(s) ? D*(sJ)l? (J = 0,2). Our predictions are Br[???(2317)l?]?=?0.50%, Br[???(2573)l?]?=?0.40%, Br[B????(2400)l?]?=?0.79%, Br[B????(2460)l?]?=?0.28%, Br[???(2400)l?]?=?0.58% and Br[???(2460)l?]?=?0.27%. .
15948978
The Pure Leptonic Decays of $D_s$ Meson and Their Radiative Corrections
The radiative corrections to the pure leptonic decay $D_s{\longrightarrow} {\ell}{{\nu}}_{\ell}$ up-to one-loop order is presented. We find the virtual photon loop corrections to $D_s{\longrightarrow} {\tau}{{\nu}}_{\tau}$ is negative and the corresponding branching ratio is larger than $3.51\times 10^{-3}$. Considering the possible experimental resolutions, our prediction of the radiative decay $D_s{\longrightarrow} {\tau}{{\nu}}_{\tau}\gamma$ is not so large as others, and the best channel to determine the $V_{cs}$ or $f_{D_s}$ is $D_s{\longrightarrow} {\mu}{{\nu}}_{\mu}{\gamma}$. How to cancel the infrared divergences appearing in the loop calculations, and the radiative decay $D_s{\longrightarrow} {\ell}{{\nu}}_{\ell}{\gamma}$ is shown precisely. It is emphasized that the radiative decay may be separated properly and may compare with measurements directly as long as the theoretical `softness' of the photon corresponds to the experimental resolutions.
119163636
Decay constants of P-wave mesons
Abstract Decay constants of P-wave mesons are computed in the framework of instantaneous Bethe–Salpeter method (Salpeter method). By analyzing the parity and possible charge conjugation parity, we give the relativistic configurations of wave functions with definite parity and possible charge conjugation parity. With these wave functions as input, the full Salpeter equations for different P-wave states are solved, and the mass spectra as well as the numerical values of wave functions are obtained. Finally we compute the leptonic decay constants of heavy–heavy and heavy–light P 0 3 , P 1 3 and P 1 1 states.
14177196
The Layer Phase in the Non-isotropic SU(3) Gauge Model at Finite Temperature
The phase structure of a non-isotropic non-Abelian SU(3) lattice gauge model at finite temperature is investigated to the third order in the variational-cumulant expansion (VCE) approach. The layer phase exists in this model in the cases of dimensions D=4, D=5 (d=D-1).
119300428
Why X(3915) is so narrow as a $\chi_{c0}(2P)$ state
New resonance X(3915) was identified as the charmonium $\chi_{c0}(2P)$ by BABAR Collaboration, but there seems still open question of this assignment: why its full width is so narrow? To answer this question, we calculate the Okubo-Zweig-Iizuka (OZI) allowed strong decays $X(3915)\to D \bar D$, where X(3915) is assigned as a $\chi_{c0}(2P)$ state, and estimate its full width in the cooperating framework of $^3/!P_0^{}$ model and the Bethe-Salpeter (BS) method using the Mandelstam Formalism, during which non-perturbative QCD effects of the hadronic matrix elements are well considered by overlapping integral over the relativistic Salpeter wave functions of the initial and finial states. We find the node structure of $\chi_{c0}(2P)$ wave function resulting in the narrow width of X(3915) and show the dependence of the decay width on the variation of the initial mass of X(3915). We point out that the rate of $\frac{\Gamma(X(3915)\to D^+ D^-)}{\Gamma(X(3915)\to D^0 \bar D^0)}$ is crucial to confirm whether X(3915) is the $\chi_{c0}(2P)$ state or not.
117632548
Studies of beam dynamics for eRHIC
We present our studies on various aspects of the beam dynamics in 'racetrack' design of the first stage electron-ion collider at RHIC (eRHIC), including transverse beam break up instabilities, energy loss due to wakefields, electron beam emittance growth and energy loss due to synchrotron radiation, electron beam losses due to Touschek effects and residue gas scattering, beam-beam effects at the interaction region and emittance growth of ion beam due to electron bunch to bunch noises. For all effects considered above, no showstopper has been found.
119956852
Energy quantization and intermittency in multiparticle production
We propose a simple model to describe the multiparticle production in high-energy hadronic interactions. As a result of energy quantization of the excitation system formed in collisions, the model naturally explains the intermittency phenomenon as well as other properties in multiparticle productions.
119180431
Empirical constraints on parton energy loss in nucleus–nucleus collisions at RHIC
Abstract We present empirical features of parton energy loss in nucleus–nucleus collisions at RHIC through studies of the spectra and nuclear modification factors ( R A A ) for charged hadrons, neutral pions ( π 0 ) and non-photonic electrons. The flat distribution of R A A at high transverse momentum ( p T ) for a given collision centrality is consistent with a scenario where parton energy loss Δ p T is proportional to p T . The centrality dependence of the parton energy loss indicates the absence of path length dependence in the magnitude of energy loss. The lack of strong path length dependence suggests a dynamical picture where the dense partonic medium undergoes rapid expansion and the density of the medium falls rapidly in the first a few Fermi interval, which may be much shorter than the full path length. Implications of the empirical constraints on the parton energy loss will also be discussed.
96428988
On the transverse momentum distribution of strange hadrons produced in relativistic heavy ion collisions
Particles with strange quark content produced in the system 1.93A·GeV58Ni on58Ni have been investigated at GSI Darmstadt with the FOPI detector system. The correlation of these produced particles was analyzed with respect to the reaction plane.Λ baryons exhibit a very pronounced sideward flow pattern which is qualitatively similar to the proton flow. However, the kaon (K+,Ks0) flow patterns are significantly different from that of the protons, and their form may be useful to restrict theoretical models on the form of the kaon potential in the nuclear medium.
118687006
Transverse Energy and Charged Particle Multiplicity in 14.6 Gev/c Proton-Nucleus Collisions.