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Title: Effective kinetic description of the expanding overoccupied glasma

Abstract

Here, we report on a numerical study of the Boltzmann equation including 2↔2 scatterings of gluons and quarks in an overoccupied glasma undergoing longitudinal expansion. We find that when a cascade of gluon number to the infrared occurs, corresponding to an infrared enhancement analogous to a transient Bose-Einstein condensate, gluon distributions qualitatively reproduce the results of classical-statistical simulations for the expanding glasma. These include key features of the distributions that are not anticipated in the “bottom-up” thermalization scenario. We also find that quark distributions, like those of gluons, satisfy self-similar scaling distributions in the overoccupied glasma. We discuss the implications of these results for a deeper understanding of the self-similarity and universality of parton distributions in the glasma.

Authors:
 [1];  [2]
  1. Univ. Heidelberg, Heidelberg (Germany)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
OSTI Identifier:
1413971
Report Number(s):
BNL-114718-2017-JA
Journal ID: ISSN 2470-0010; PRVDAQ
Grant/Contract Number:
SC0012704
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 95; Journal Issue: 9; Journal ID: ISSN 2470-0010
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Tanji, Naoto, and Venugopalan, Raju. Effective kinetic description of the expanding overoccupied glasma. United States: N. p., 2017. Web. doi:10.1103/PhysRevD.95.094009.
Tanji, Naoto, & Venugopalan, Raju. Effective kinetic description of the expanding overoccupied glasma. United States. doi:10.1103/PhysRevD.95.094009.
Tanji, Naoto, and Venugopalan, Raju. 2017. "Effective kinetic description of the expanding overoccupied glasma". United States. doi:10.1103/PhysRevD.95.094009.
@article{osti_1413971,
title = {Effective kinetic description of the expanding overoccupied glasma},
author = {Tanji, Naoto and Venugopalan, Raju},
abstractNote = {Here, we report on a numerical study of the Boltzmann equation including 2↔2 scatterings of gluons and quarks in an overoccupied glasma undergoing longitudinal expansion. We find that when a cascade of gluon number to the infrared occurs, corresponding to an infrared enhancement analogous to a transient Bose-Einstein condensate, gluon distributions qualitatively reproduce the results of classical-statistical simulations for the expanding glasma. These include key features of the distributions that are not anticipated in the “bottom-up” thermalization scenario. We also find that quark distributions, like those of gluons, satisfy self-similar scaling distributions in the overoccupied glasma. We discuss the implications of these results for a deeper understanding of the self-similarity and universality of parton distributions in the glasma.},
doi = {10.1103/PhysRevD.95.094009},
journal = {Physical Review D},
number = 9,
volume = 95,
place = {United States},
year = 2017,
month = 5
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on May 19, 2018
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