119103070
Pseudorapidity dependence of anisotropic flows in relativistic heavy-ion collisions
Abstract The pseudorapidity dependence of anisotropic flows v 1 , v 2 , v 3 and v 4 of charged hadrons in heavy-ion collisions at the relativistic heavy-ion collider is studied in a multi-phase transport model. We find that while the string melting scenario, in which hadrons that are expected to be formed from initial strings are converted to their valence quarks and antiquarks, can explain the measured p T -dependence of v 2 and v 4 of charged hadrons at midrapidity with a parton scattering cross section of about 10 mb, the scenario without string melting reproduces better the recent data on v 1 and v 2 of charged hadrons at large pseudorapidity in Au + Au collisions at s = 200 A GeV . Our results thus suggest that a partonic matter is formed during early stage of relativistic heavy-ion collisions only around midrapidity and that strings remain dominant at large rapidities. The p T -dependence of v 1 , v 2 , v 3 and v 4 for charged hadrons at forward pseudorapidity is also predicted, and we find that while v 1 and v 2 are appreciable at large pseudorapidity the higher-order anisotropic flows v 3 and v 4 are essentially zero.
15108148
Systematic study of the pi(-)/pi(+) ratio in heavy-ion collisions with the same neutron/proton ratio but different masses
National Natural Science Foundation of China 10675148 
10635080 
10575071 
10675082 
MOE of China NCET-05-0392 
Shanghai Rising-Star Program 06QA14024 
SEM of China 
National Basic Research Program of China 2007CB815004 
US National Science Foundation PHY-0652548 
PHY-0757839 
Research Corporation 7123 
Texas Coordinating Board of Higher Education 0035650004- 2007
120983580
Isospin dependent Pauli blocking and nucleon mean free path in isospin-asymmetric nuclear matter
118388447
Correlations between the nuclear breathing mode energy and properties of asymmetric nuclear matter
Based on microscopic Hartree–Fock + random phase approximation calculations with Skyrme interactions, we study the correlations between the nuclear breathing mode energy EISGMR and properties of asymmetric nuclear matter with a recently developed analysis method. Our results indicate that the EISGMR of 208Pb exhibits moderate correlations with the density slope L of the symmetry energy and the isoscalar nucleon effective mass m*s, 0 besides a strong dependence on the incompressibility K0 of symmetric nuclear matter. Using the present empirical values of L = 60 ± 30 MeV and m*s, 0 = (0.8 ± 0.1)m, we obtain a theoretical uncertainty of about ±16 MeV for the extraction of K0 from the EISGMR of 208Pb. Furthermore, we find that the EISGMR difference between 100Sn and 132Sn strongly correlates with L and thus provides a potentially useful probe of the symmetry energy.
44780624
Partonic Effects on Higher-Order Anisotropic Flows in Relativistic Heavy-Ion Collisions
Higher-order anisotropic flows ${v}_{4}$ and ${v}_{6}$ of charged hadrons in heavy-ion collisions at the Relativistic Heavy Ion Collider are studied in a multiphase transport model that has previously been used successfully for describing the elliptic flow ${v}_{2}$ of identified hadrons in these collisions. We find that the same parton scattering cross section of about $10\phantom{\rule{0.3em}{0ex}}\text{mb}$ used in explaining the measured ${v}_{2}$ of charged hadrons can also reproduce the recent data on their ${v}_{4}$ and ${v}_{6}$ from $\text{Au}+\text{Au}$ collisions at $\sqrt{s}=200A\phantom{\rule{0.3em}{0ex}}\text{GeV}$. It is further found that ${v}_{4}$ is a more sensitive probe of the initial partonic dynamics in these collisions than ${v}_{2}$. Moreover, higher-order parton anisotropic flows are non-negligible and satisfy the scaling relation ${v}_{n,q}({p}_{T})\ensuremath{\sim}{v}_{2,q}^{n∕2}({p}_{T})$, which leads naturally to the observed similar scaling relation among hadron anisotropic flows when the coalescence model is used to describe hadron production from the partonic matter.
119234702
TRITON-3HE RELATIVE AND DIFFERENTIAL FLOWS AND THE HIGH DENSITY BEHAVIOR OF NUCLEAR SYMMETRY ENERGY
Using a transport model coupled with a phase-space coalescence after-burner we study the triton-3He relative and differential transverse flows in semi-central 132Sn + 124Sn reactions at a beam energy of 400 MeV/nucleon. We find that the triton-3He pairs carry interesting information about the density dependence of the nuclear symmetry energy. The t-3He relative flow can be used as a particularly powerful probe of the high-density behavior of the nuclear symmetry energy.
118395281
NLO corrections to $\chi_{bJ}$ to two-$J/\psi$ exclusive decay processes
The next-to-leading order QCD corrections for $\chi_{bJ}$, the p-wave bottomonium, to $J/\psi$ pair decay processes are evaluated utilizing NRQCD factorization formalism. The scale dependence of $\chi_{b2}\rightarrow J/\psi J/\psi$ process is depressed with NLO corrections, and hence the uncertainties in the leading order results are greatly reduced. The total branch ratios are found to be the order of $10^{-5}$ for all three $\chi_{bJ}\rightarrow J/\psi J/\psi$ processes, indicating that they are observable in the LHC and super-B experiments.
137374294
Preliminary Lattice Design of the SSRF Storage Ring
119110745
Causal loops in the theory of relative locality
We find that relative locality, a recently proposed Planck-scale deformation of special relativity, suffers from the existence of causal loops. A simple and general construction of such on-shell loop processes is studied. We then show that even in one of the weakest deformations of the Poincar\'e group in relative locality, causality can be violated.
119289860
P-wave quarkonium decays to meson pairs
A bstractThe processes of p-wave Quarkonium exclusive decays to two mesons are investigated, in which the final state vector mesons with various polarizations are considered separately. In the calculation, the initial heavy quarkonia are treated in the framework of non-relativistic quantum chromodynamics, whereas for light mesons, the light cone distribution amplitudes up to twist-3 are employed. It turns out that the higher twist contribution is significant and provides a possible explanation for the observation of the hadron helicity selection rule violated processes χc1→ φφ, ωω by the BESIII collaboration in recently. We also evaluate the χb1→ J/ψJ/ψ process and find that its branching ratio is big enough to be measured at the B-factories.
122248926
Simulation study of beam-beam effects
The Beijing Electron-Positron Collider (BEPC) will be upgraded to BEPCII, and the luminosity will be about 100 times higher. We developed a three-dimensional strong-strong PIC code to study the beam-beam effects in BEPCII. The transportation through the arc is the same as that in Hirata's weak-strong code. The beam-beam force is computed directly by solving the Poisson equation using the Fourier analysis and cyclic reduction method, and the boundary potential is computed by circular convolution. The finite bunch length effect is included by longitudinal slices. An interpolation scheme is used to reduce the required slice number in simulations. The standard message passing interface is used to parallelize the code. The computing time increases linearly with (n+1), where n is the slice number. The calculated luminosity of BEPCII at the design working point is similar to 50% of the design value. The best area in the tune space is near (0.505,0.57) according to the survey, where the luminosity is similar to 80% of the design.