English

Rapidity equilibration and longitudinal expansion at RHIC

High Energy Physics - Phenomenology 2009-09-29 v3

Abstract

The evolution of net-proton rapidity spectra with sqrt(s_NN) in heavy relativistic systems is proposed as an indicator for local equilibration and longitudinal expansion. In a Relativistic Diffusion Model, bell-shaped distributions in central collisions at AGS energies and double-humped nonequilibrium spectra at SPS show pronounced longitudinal collective expansion when compared to the available data. The broad midrapidity valley recently discovered at RHIC in central Au+Au collisions at sqrt(s_NN) = 200 GeV indicates rapid local equilibration which is most likely due to deconfinement, and fast longitudinal expansion of the locally equilibrated subsystem. A prediction is made for Au+Au at sqrt(s_NN)= 62.4 GeV.

Keywords

Cite

@article{arxiv.hep-ph/0502123,
  title  = {Rapidity equilibration and longitudinal expansion at RHIC},
  author = {Georg Wolschin},
  journal= {arXiv preprint arXiv:hep-ph/0502123},
  year   = {2009}
}

Comments

11 pages, 1 table, 2 figures; changes/additions in text, table, figs