Elastic parton scattering and non-statistical event-by-event mean-pt fluctuations in Au + Au collisions at RHIC

TL;DR

This paper investigates how elastic parton scattering influences non-statistical mean-p_t fluctuations in Au + Au collisions at RHIC, demonstrating that these fluctuations can serve as probes of initial partonic dynamics.

Contribution

It shows that in-medium elastic parton scattering significantly affects mean-p_t fluctuations and that these fluctuations can be used to probe initial partonic conditions in heavy-ion collisions.

Findings

AMPT with string-melting reproduces STAR data at 130 GeV with sigma_p=10 mb.

Fluctuation data at 200 GeV are well matched with sigma_p between 6 and 10 mb.

Elastic parton scattering is a major contributor to observed mean-p_t fluctuations.

Abstract

Non-statistical event-by-event mean-pt fluctuations in Au + Au collisions at sqrt(s_NN) = 130 and 200 GeV are analyzed in AMPT with string-melting, and the results are compared with STAR data. The analysis suggests that in-medium elastic parton scattering may contribute greatly to the mean-p_t fluctuations in relativistic heavy-ion collisions. Furthermore, it is demonstrated that non-statistical event-by-event mean-pt fluctuations can be used to probe the initial partonic dynamics in these collisions. The comparison shows that with an in-medium elastic parton scattering cross section sigma_p=10 mb, AMPT with string-melting can well reproduce sqrt(s_NN) = 130 GeV data on the centrality dependence of non-statistical event-by-event mean-pt fluctuations. The comparison also shows that the fluctuation data for sqrt(s_NN) = 200 GeV Au + Au collisions can be well reproduced with sigma_p between 6 and 10 mb.