An alternative model of jet suppression at RHIC energies

Abstract

We propose a simple Glauber-type mechanism for suppression of jet production up to transverse momenta of about 10 GeV/c at RHIC. For processes in this kinematic region, the formation time is smaller than the interval between two successive hard partonic collisions and the subsequent collision influences the jet production. Number of jets then roughly scales with the number of participants. Proportionality to the number of binary collisions is recovered for very high transverse momenta. The model predicts suppression of jet production in d+Au collisions at RHIC.

Transverse-Momentum and Collision-Energy Dependence of High-pTHadron Suppression inAu+AuCollisions at Ultrarelativist

“…The magnitude of suppression is fitted to the central collision data in the pQCD models but is predicted in the saturation calculation. Attenuation of initial jet formation due to multiple nucleon interactions [13] generates an increase in partonic R AA p T for central collisions of a factor 2 in 5 < E T <12 GeV. A similar p T dependence would be expected for high p T hadrons, in contrast to observations.…”

“…Several striking high p T phenomena have been observed at the BNL Relativistic Heavy Ion Collider (RHIC) [3][4][5][6][7], including strong suppression of inclusive hadron production [3][4][5]. These phenomena are consistent with large partonic energy loss in high energy density matter [1,[8][9][10][11] though other mechanisms have been proposed, including gluon saturation in the initial nuclear wave function [12], attenuation of jet formation in cold nuclear matter [13], and scattering of fragmentation hadrons [14]. Additional measurements are required to discriminate among these pictures and to isolate effects due to final-state partonic energy loss.…”

Calculating quenching weights

“…Models have been proposed which account for hadronic quenching without taking recourse to parton energy loss. Instead, these models invoke string percolation 52 , small hadronization time arguments 53 , saturation physics 54 , the dominance of parton recombination over parton fragmentation 55 , or initial state formation time arguments 56 . The consistency and applicability of these models is currently under debate.…”

High-pThadron spectra at RHIC: an overview

“…Although the data in figure 3 compare quite well with models incorporating final-state partonic energy loss, final-state hadronic re-scattering may play some role in generating the observed suppression and many theoretical investigations of this possibility have been undertaken [28,29,31]. In figure 5, a comparison is made between RHIC data and a hadron-string-dynamics (HSD) model which incorporates quark, diquark, string and hadronic interactions with the medium [30].…”