Balance functions from Au+Au, d+Au, and p+p collisions at √sNN=200 GeV

Aggarwal, M. M. and Planinić, Mirko and Poljak, Nikola and Zoulkarneeva, Y. (STAR Collaboration) (2010) Balance functions from Au+Au, d+Au, and p+p collisions at √sNN=200 GeV. Physical Review C, 82 (2). pp. 24905-16. ISSN 0556-2813

[img]
Preview
PDF - Published Version
Language: English

Download (1MB) | Preview

Abstract

Balance functions have been measured for charged-particle pairs, identified charged-pion pairs, and identified charged-kaon pairs in Au+Au, d+Au, and p+p collisions at √sNN=200 GeV at the Relativistic Heavy Ion Collider using the STAR detector. These balance functions are presented in terms of relative pseudorapidity, Δη, relative rapidity, Δy, relative azimuthal angle, Δϕ, and invariant relative momentum, qinv. For charged-particle pairs, the width of the balance function in terms of Δη scales smoothly with the number of participating nucleons, while hijing and urqmd model calculations show no dependence on centrality or system size. For charged-particle and charged-pion pairs, the balance functions widths in terms of Δη and Δy are narrower in central Au+Au collisions than in peripheral collisions. The width for central collisions is consistent with thermal blast-wave models where the balancing charges are highly correlated in coordinate space at breakup. This strong correlation might be explained by either delayed hadronization or limited diffusion during the reaction. Furthermore, the narrowing trend is consistent with the lower kinetic temperatures inherent to more central collisions. In contrast, the width of the balance function for charged-kaon pairs in terms of Δy shows little centrality dependence, which may signal a different production mechanism for kaons. The widths of the balance functions for charged pions and kaons in terms of qinv narrow in central collisions compared to peripheral collisions, which may be driven by the change in the kinetic temperature.

Item Type: Article
Keywords: p p, interaction heavy ion, scattering deuteron gold charged particle, multiple production charge correlation correlation, two-pion correlation, (2K) rapidity, correlation angular correlation impact parameter, dependence quantum molecular dynamics, relativistic blast wave STAR experimental results Brookhaven RHIC Coll 200 GeV-cms/nucleon
Date: August 2010
Subjects: NATURAL SCIENCES > Physics
Additional Information: Copyright (2010) by the American Physical Society.
Divisions: Faculty of Science > Department of Physics
Project code: 119-0982887-1006
Publisher: American Physical Society
Depositing User: Gordana Stubičan Ladešić
Date Deposited: 05 Jun 2014 12:56
Last Modified: 24 Feb 2016 15:29
URI: http://digre.pmf.unizg.hr/id/eprint/2272

Actions (login required)

View Item View Item