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arXiv · 2101.03791

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

S. Demirci·T. Lappi·S. Schlichting
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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.

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S. Demirci, T. Lappi, S. Schlichting. 2021-01-11. Hot spots and gluon field fluctuations as causes of eccentricity in small systems. https://doi.org/10.1103/physrevd.103.094025

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