Suppression of high $p_T$ hadron spectra in $p+A$ collisions

TL;DR

This paper investigates how multiple parton scatterings and correlations in high-energy proton-nucleus collisions lead to the suppression of high transverse momentum hadron spectra, using the HIJING 2.1 Monte Carlo model.

Contribution

It introduces a detailed modeling of multi-parton correlations and their impact on hadron spectra suppression in $p+A$ collisions at RHIC and LHC energies.

Findings

Suppression of high $p_T$ hadron spectra observed.

Multi-parton correlations significantly affect final hadron distributions.

Nuclear shadowing and transverse momentum broadening contribute to suppression.

Abstract

Multiple hard and semi-hard parton scatterings in high-energy $p+A$ collisions involve multi-parton correlation in both momentum and flavor inside the projectile proton which will lead to modification of the final hadron spectra relative to that in $p+p$ collisions. Such modification of final hadron transverse momentum spectra in $p+A$ collisions is studied within HIJING 2.1 Monte Carlo model which includes nuclear shadowing of the initial parton distributions and transverse momentum broadening. Multi-parton flavor and momentum correlation inside the projectile are incorporated through flavor and momentum conservation which are shown to modify the flavor content and momentum spectra of final partons and most importantly lead to suppression of large $p_{T}$ hadron spectra in $p+A$ collisions at both RHIC and LHC energies.