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Title: Unveiling saturation effects from nuclear structure function measurements at the EIC

Abstract

Here, we analyze the possibility of extracting a clear signal of non-linear parton saturation effects from future measurements of nuclear structure functions at the Electron–Ion Collider (EIC), in the small-x region. Our approach consists in generating pseudodata for electron-gold collisions, using the running-coupling Balitsky–Kovchegov evolution equation, and in assessing the compatibility of these saturated pseudodata with existing sets of nuclear parton distribution functions (nPDFs), extrapolated if necessary. The level of disagreement between the two is quantified by applying a Bayesian reweighting technique. This allows to infer the parton distributions needed in order to describe the pseudodata, which we find quite different from the actual distributions, especially for sea quarks and gluons. This tension suggests that, should saturation effects impact the future nuclear structure function data as predicted, a successful refitting of the nPDFs may not be achievable, which would unambiguously signal the presence of non-linear effects.

Authors:
 [1];  [2];  [3]
  1. Univ. Paris-Saclay, Palaiseau (France)
  2. Univ. de Santiago de Compostela, Galicia (Spain)
  3. Univ. de Santiago de Compostela, Galicia (Spain); Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States). Relativistic Heavy Ion Collider (RHIC)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
OSTI Identifier:
1372407
Report Number(s):
BNL-114811-2017-JA
Journal ID: ISSN 0370-2693; R&D Project: PO 004; KB0202012; TRN: US1800366
Grant/Contract Number:
SC0012704
Resource Type:
Journal Article: Published Article
Journal Name:
Physics Letters. Section B
Additional Journal Information:
Journal Volume: 772; Journal Issue: C; Journal ID: ISSN 0370-2693
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; Relativistic Heavy Ion Collider

Citation Formats

Marquet, Cyrille, Moldes, Manoel R., and Zurita, Pia. Unveiling saturation effects from nuclear structure function measurements at the EIC. United States: N. p., 2017. Web. doi:10.1016/j.physletb.2017.07.035.
Marquet, Cyrille, Moldes, Manoel R., & Zurita, Pia. Unveiling saturation effects from nuclear structure function measurements at the EIC. United States. doi:10.1016/j.physletb.2017.07.035.
Marquet, Cyrille, Moldes, Manoel R., and Zurita, Pia. 2017. "Unveiling saturation effects from nuclear structure function measurements at the EIC". United States. doi:10.1016/j.physletb.2017.07.035.
@article{osti_1372407,
title = {Unveiling saturation effects from nuclear structure function measurements at the EIC},
author = {Marquet, Cyrille and Moldes, Manoel R. and Zurita, Pia},
abstractNote = {Here, we analyze the possibility of extracting a clear signal of non-linear parton saturation effects from future measurements of nuclear structure functions at the Electron–Ion Collider (EIC), in the small-x region. Our approach consists in generating pseudodata for electron-gold collisions, using the running-coupling Balitsky–Kovchegov evolution equation, and in assessing the compatibility of these saturated pseudodata with existing sets of nuclear parton distribution functions (nPDFs), extrapolated if necessary. The level of disagreement between the two is quantified by applying a Bayesian reweighting technique. This allows to infer the parton distributions needed in order to describe the pseudodata, which we find quite different from the actual distributions, especially for sea quarks and gluons. This tension suggests that, should saturation effects impact the future nuclear structure function data as predicted, a successful refitting of the nPDFs may not be achievable, which would unambiguously signal the presence of non-linear effects.},
doi = {10.1016/j.physletb.2017.07.035},
journal = {Physics Letters. Section B},
number = C,
volume = 772,
place = {United States},
year = 2017,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.physletb.2017.07.035

Citation Metrics:
Cited by: 1work
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  • Here, we analyze the possibility of extracting a clear signal of non-linear parton saturation effects from future measurements of nuclear structure functions at the Electron–Ion Collider (EIC), in the small-x region. Our approach consists in generating pseudodata for electron-gold collisions, using the running-coupling Balitsky–Kovchegov evolution equation, and in assessing the compatibility of these saturated pseudodata with existing sets of nuclear parton distribution functions (nPDFs), extrapolated if necessary. The level of disagreement between the two is quantified by applying a Bayesian reweighting technique. This allows to infer the parton distributions needed in order to describe the pseudodata, which we find quitemore » different from the actual distributions, especially for sea quarks and gluons. This tension suggests that, should saturation effects impact the future nuclear structure function data as predicted, a successful refitting of the nPDFs may not be achievable, which would unambiguously signal the presence of non-linear effects.« less
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