English

Upsilon Productions at STAR

Nuclear Experiment 2010-05-25 v1

Abstract

The Υ(1S+2S+3S)e+e\Upsilon(1S+2S+3S)\to e^{+}e^{-} cross section is measured at mid-rapidity (yy) in p+pp+p collisions and in d+Au+Au collisions at center-of-mass energy s\sqrt{s} = 200 GeV with the STAR detector at RHIC. In p+pp+p, the measured cross section is found to be consistent with the world data trend as a function of s\sqrt{s}, in agreement with the Color Evaportaion Model (CEM), and underestimated by the Color Singlet Model (CSM) up to the Next-to-Leading-Order Quantum Chromodynamics (NLO QCD) calculations. In d+AuAu, the measured cross section is in agreement with the CEM prediction with anti-shadowing effects, and the nuclear modification factor indicates that Υ(1S+2S+3S)\Upsilon(1S+2S+3S) production follows binary scaling within the current uncertainties. These measurements provide a benchmark for the future measurements of Υ\Upsilon production in Au+AuAu+Au collisions.

Keywords

Cite

@article{arxiv.1005.4100,
  title  = {Upsilon Productions at STAR},
  author = {A. M. Hamed},
  journal= {arXiv preprint arXiv:1005.4100},
  year   = {2010}
}

Comments

4 pages, 6 figures, Lake Louise Winter Institute 2010, 15th-20th February 2010 Alberta, Canada

R2 v1 2026-06-21T15:26:28.304Z