121116255
EMC effect and the distortion of the vacuum in nuclei
Based on the argument that the bag radius of a bounded nucleon is larger than that of a free one due to the change of vacuum property in nucleus, a good fit is obtained for the EMC effect.
118652542
Study of triangular flow v3 in Au+Au and Cu+Cu collisions with a multiphase transport model
We studied the relation between the initial geometry anisotropy and the anisotropic flow in a multiphase transport model for both Au+Au and Cu+Cu collisions at = 200 GeV. It is found that unlike the elliptic flow v2, little centrality dependence of the triangular flow v3 is observed. After removing the initial geometry effect, v3/e3 increases with the transverse particle density, which is similar to v2/e2. The transverse momentum (pT) dependence of v3 from identified particles is qualitatively similar to the pT dependence of v2.
15711757
Thermal Equilibrium and Non-uniform Longitudinal Flow in Relativistic Heavy Ion Collisions
A model with non-uniform flow in the longitudinal direction is proposed for the relativistic heavy-ion collisions and compared with the 14.6 A GeV/c Si-Al and 10.8 A GeV/c Au-Au collision data. The stronger influence of transparency on the distribution of heavier produced particles and the larger stopping in the heavier collision system are accounted for by using a new geometrical parameterization picture. The central dips in the proton and deuteron rapidity distributions for Si-Al collision are reproduced.
120498489
Elliptic flow in a hadron transport model
We present elliptic flow v2 as a function of freeze-out time, transverse momentum for π, K, nucleon, Λ, Ξ and Ω in Au+Au collisions at within two transport approaches (RQMD and UrQMD). The presence of mass ordering and NCQ scaling in the string-hadron model suggests that hadronic interactions do contribute to the observed particle-type dependence of v2 as well.
17224426
New results for hadronic collisions in the framework of the Parton-Based Gribov-Regge Theory
Abstract We recently proposed a new approach to high energy nuclear scattering, which treats hadronic collisions in a sophisticated way. Demanding theoretical consistency as a minimal requirement for a realistic model, we provide a solution for the energy conservation, screening problems and identical elementary interactions, the so-called “Parton-Based Gribov-Regge Theory” including enhanced diagrams. We can now present some of our results for SPS and RHIC energies.
1752055
On transverse momentum event–by–event fluctuations in string hadronic models
Abstract. Transverse momentum event–by–event fluctuations are studied within the string–hadronic model of high energy nuclear collisions, LUCIAE. Data on non–statistical $p_T$ fluctuations in p+p interactions are reproduced. Fluctuations of similar magnitude are predicted for nucleus–nucleus collisions, in contradiction to the preliminary NA49 results. The introduction of a string clustering mechanism (Firecracker Model) leads to a further, significant increase of $p_T$ fluctuations for nucleus–nucleus collisions. Secondary hadronic interactions, as implemented in LUCIAE, cause only a small reduction of $p_T$ fluctuations.
119110786
Statistical interpretation of the spatial distribution of current 130 GeV gamma-ray line signal within the dark matter annihilation scenario
Recently, several groups identified a tentative gamma-ray line signal with energy similar to 130 GeV in the central Galaxy from the Fermi-EAT data. Such a gamma-ray line can be interpreted as the signal of dark matter annihilation. However, the offset similar to 220 pc (1.5 degrees) of the center of the most prominent signal region from the Galactic center Sgr A* has been thought to challenge the dark matter annihilation interpretation. Considering the fact that such a 130 GeV gamma-ray line signal consists of only similar to 14 photons, we suggest that the "imperfect" consistency of these photons with the expected dark matter distribution is due to the limited statistics. The offset will be smaller as more signal photons have been collected in the near future. Our Monte Carlo simulation supports the above speculation. (c) 2012 Elsevier B.V. All rights reserved.
123132096
Observational constraints on the early dark energy model
Dark energy can be studied by its influence on the expansion of the Universe. We investigate current constraints on early dark energy (EDE) achievable by the combined observational data from type Ia supernovae (557), baryon acoustic oscillations, the current cosmic microwave background and the observed Hubble parameter. We find that combining these data sets provides powerful constraints on early dark energy and the best fit values of the parameters in 68% and 95% confidence-level regions are: Omega(m0) = 0.2897(-0.0138-0.0194)(+0.0149+0.0207) Omega(e) = 0.0125(-0.0129-0.0129)(+0.0272+0.0381), omega(0) = -1.0415(-0.109-0.1604)(+0.0891+0.1182), and h = 0.6988(-0.0058-0.0081)(+0.0059+0.0083).