Azimuthal anisotropy in Cu plus Au collisions at root s(NN)=200 GeV

0492102 - ÚJF 2019 RIV US eng J - Článek v odborném periodiku
Adamczyk, L. - Adams, J. R. - Adkins, J. K. - Agakishiev, G. - Aggarwal, M. M. - Bielčík, J. - Bielčíková, Jana - Chaloupka, P. - Federič, Pavol - Federičová, P. - Harlenderová, A. - Kocmánek, Martin - Kvapil, J. - Lidrych, J. - Rusňák, Jan - Rusňáková, O. - Šaur, Miroslav - Šimko, Miroslav - Šumbera, Michal - Trzeciak, B. A. … celkem 347 autorů
Azimuthal anisotropy in Cu plus Au collisions at root s(NN)=200 GeV.
Physical Review C. Roč. 98, č. 1 (2018), č. článku 014915. ISSN 2469-9985. E-ISSN 2469-9993
Grant CEP: GA MŠMT EF16_013/0001569
Institucionální podpora: RVO:61389005
Klíčová slova: STAR * heavy ion collisions * energy
Obor OECD: Nuclear physics
Impakt faktor: 3.132, rok: 2018

The azimuthal anisotropic flow of identified and unidentified charged particles has been systematically studied in Cu+Au collisions at root s(NN) = 200 GeV for harmonics n = 1-4 in the pseudorapidity range vertical bar eta vertical bar < 1. The directed flow in Cu+Au collisions is compared with the rapidity-odd and, for the first time, the rapidity-even components of charged particle directed flow in Au+Au collisions at root s(NN) = 200 GeV. The slope of the directed flow pseudorapidity dependence in Cu+Au collisions is found to be similar to that in Au+Au collisions, with the intercept shifted toward positive pseudorapidity values, i.e., the Cu-going direction. The mean transverse momentum projected onto the spectator plane p(x) in Cu+Au collision also exhibits approximately linear dependence on pseudorapidity with the intercept at about eta approximate to -0.4 (shifted from zero in the Au-going direction), closer to the rapidity of the Cu+Au system center of mass. The observed dependencies find a natural explanation in a picture of the directed flow originating partly due the 'tilted source' and partly due to the asymmetry in the initial density distribution. A charge dependence of p(x) was also observed in Cu+Au collisions, consistent with an effect of the initial electric field created by charge difference of the spectator protons in two colliding nuclei. The rapidity-even component of directed flow in Au+Au collisions is close to that in Pb+Pb collisions at root s(NN) = 2.76 TeV, indicating a similar magnitude of dipolelike fluctuations in the initial-state density distribution. Higher harmonic flow in Cu+Au collisions exhibits similar trends to those observed in Au+Au and Pb+Pb collisions and is qualitatively reproduced by a viscous hydrodynamic model and a multiphase transport model. For all harmonics with n >= 2 we observe an approximate scaling of v(n) with the number of constituent quarks, this scaling works as well in Cu+Au collisions as it does in Au+Au collisions.
Trvalý link: http://hdl.handle.net/11104/0285664