High-p_T pi^0 suppression in Au+Au collisions at sqrt(s_NN) = 200 GeV

TL;DR

This paper reports the measurement of neutral pion suppression at high transverse momentum in gold-gold collisions at 200 GeV, revealing significant suppression in central collisions that increases with p_T and centrality.

Contribution

First detailed measurement of high-p_T pi^0 suppression across multiple centrality classes in Au+Au collisions at RHIC.

Findings

Significant suppression of pi^0 yields in central collisions

Suppression increases with p_T and collision centrality

Deficit reaches a factor of ~6 at high p_T in the most central collisions

Abstract

Neutral pions with p_T = 1 - 8 GeV/c have been measured for 9 different centrality classes in Au+Au collisions at sqrt(s_NN) = 200 GeV by the PHENIX experiment at RHIC. The pi^0 multiplicity in central reactions is significantly below the binary collision scaled yields from both peripheral Au+Au and pp reactions. The observed suppression sets in for the 50-70% centrality class and increases with p_T and centrality. For the most central bin, the deficit amounts to a factor ~2.5 at p_T ~ 2 GeV/c gradually increasing to a factor ~6 at p_T ~ 8 GeV/c.