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arXiv · 1601.03070

Direct photon production and jet energy-loss in small systems

Chun Shen·Chanwook Park·Jean-François Paquet·Gabriel S. Denicol·Sangyong Jeon·Charles Gale
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Abstract

Two types of penetrating probes, direct photon and QCD jets, are investigated in the background of a small and rapidly expanding droplet of quark-gluon plasma. The additional thermal electromagnetic radiation results in a $\sim$50\% enhancement of the direct photons. In high multiplicity p+Pb collisions, jets can lose a sizeable fraction of their initial energy, leading to a charged hadron $R_\mathrm{pA}$ of $\sim$0.8 at a transverse momentum around 10\,GeV. Those two proposed measurements can help understand the apparent collective behaviour observed in small collision systems.

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Chun Shen, Chanwook Park, Jean-François Paquet, Gabriel S. Denicol, Sangyong Jeon, Charles Gale. 2016-01-12. Direct photon production and jet energy-loss in small systems. https://arxiv.org/abs/1601.03070

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