Hot spots and gluon field fluctuations as causes of eccentricity in small systems

Abstract

We calculate eccentricities in high energy proton-nucleus collisions, by calculating correlation functions of the energy density field of the Glasma immediately after the collision event at proper time tau = 0. We separately consider the effects of color charge and geometrical hot spot fluctuations, analytically performing the averages over both in a dilute-dense limit. We show that geometric fluctuations of hot spots inside the proton are the dominant source of eccentricity whereas color charge fluctuations only give a negligible correction. The size and number of hot spots are the most important parameters characterizing the eccentricities.

21 pages, 9 figures

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• Continuous description of fluctuating eccentricities

Cited by in corpus (11)

• Color charge correlations in the proton at NLO: beyond geometry based intuition
• Development of transverse flow at small and large opacities in conformal kinetic theory
• Rapidity dependence of initial state geometry and momentum correlations in p+Pb collisions
• Proton hot spots and exclusive vector meson production
• Quark and gluon entanglement in the proton on the light cone at intermediate $x$
• Physical characteristics of glasma from the earliest stage of relativistic heavy ion collisions
• Opacity dependence of transverse flow, pre-equilibrium and applicability of hydrodynamics in heavy-ion collisions
• Energy-momentum tensor of the dilute (3+1)D Glasma
• Collective dynamics in heavy and light-ion collisions -- I) Kinetic Theory vs. Hydrodynamics
• Evolution of eccentricities induced by geometrical and quantum fluctuations in proton-nucleus collisions
• Parton evolution time dependent transverse shape asymmetry in peripheral Pb-Pb and p-Pb collisions at 5.02 TeV