scholarly journals Specificities of RHIC heavy ion collisions probed by strange particles measured by the STAR experiment

2007 ◽  
Author(s):  
Christelle Roy
2018 ◽  
Vol 171 ◽  
pp. 18015
Author(s):  
Xinjie Huang

In these proceedings, we present the latest measurements of J/ψ and ϒ by the STAR experiment. The J/ψ and ϒ production measured in p+p collisions provide new baselines for similar measurements in Au+Au collisions, while the measurements in p+Au collisions can help quantify the cold nuclear matter effects. The J/ψ υ2 is measured in both U+U and Au+Au collisions to place constraints on the amount of J/ψ arising from recombination of deconfined charm and anti-charm pairs. Furthermore, the nuclear modification factors for ground and excited ϒ states as a function of transverse momentum and centrality are presented, and compared to those measured at the LHC as well as to theoretical calculations.


2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
M. G. de Paoli ◽  
D. P. Menezes

It is expected that the magnetic fields in heavy ion collisions are very high. In this work, we investigate the effects of a strong magnetic field on particle ratios within a thermal model of particle production. We model matter as a free gas of baryons and mesons under the influence of an external magnetic field varying from zero to30mπ2through an  χ2fitting to some data sets of the STAR experiment. For this purpose, we use the Dirac, Rarita-Schwinger, Klein-Gordon, and Proca equations subject to magnetic fields in order to obtain the energy expressions and the degeneracy for spin 1/2, spin 3/2, spin 0, and spin 1 particles, respectively. Our results show that, if the magnetic field can be considered as slowly varying and leaves its signature on the particle yields, a field of the order of6mπ2produces an improved fitting to the experimental data as compared to the calculations without magnetic field.


2002 ◽  
Vol 28 (7) ◽  
pp. 1977-1980 ◽  
Author(s):  
L V Bravina ◽  
L P Csernai ◽  
Amand Faessler ◽  
C Fuchs ◽  
E E Zabrodin

2013 ◽  
Vol 22 (06) ◽  
pp. 1350041 ◽  
Author(s):  
V. A. OKOROKOV

In this paper, two combinations of correlators are defined in order to investigate the evolution of possible [Formula: see text] invariance violation in strong interactions with initial energy for heavy-ion collisions. These combinations correspond to absolute and relative asymmetry of distribution of electrically charge particles with respect to the reaction plane in heavy-ion collisions. Energy dependence of parameters under study was derived from data of STAR and ALICE experiments. Significant decreasing both absolute and relative asymmetry is observed at energies [Formula: see text]. This feature agrees qualitatively with other results of stage-I beam energy scan program in STAR experiment. General behavior of dependence of absolute asymmetry on initial energy agrees reasonably with behavior of similar dependence of Chern–Simons diffusion rate calculated at different values of external Abelian magnetic field. The observed behavior of parameters under study versus energy can be considered as indication on possible transition to predominance of hadronic states over quark–gluon degrees of freedom in the mixed phase created in heavy-ion collisions at intermediate energies.


Sign in / Sign up

Export Citation Format

Share Document