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Title: Effect of the fluctuating proton size on the study of the chiral magnetic effect in proton-nucleus collisions

High energy proton-nucleus (pA) collisions provide an important constraint on the study of the chiral magnetic effect in QCD matter. Naively, in pA collisions one expects no correlation between the orientation of event plane as reconstructed from the azimuthal distribution of produced hadrons and the orientation of magnetic field. If this is the case, any charge-dependent hadron correlations can only result from the background. Nevertheless, in this paper we point out that in high multiplicity pA collisions a correlation between the magnetic field and the event plane can appear. This is because triggering on the high hadron multiplicity amounts to selecting Fock components of the incident proton with a large number of partons that are expected to have a transverse size much larger than the average proton size. We introduce the effect of the fluctuating proton size in the Monte Carlo Glauber model and evaluate the resulting correlation between the magnetic field and the second-order event plane in both pA and nucleus-nucleus (AA) collisions. The fluctuating proton size is found to result in a significant correlation between magnetic field and the event plane in pA collisions, even though the magnitude of the correlation is still much smaller than in AAmore » collisions. Here, this result opens a possibility of studying the chiral magnetic effect in small systems.« less
 [1] ;  [2] ;  [2] ;  [2]
  1. Stony Brook Univ., Stony Brook, NY (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
  2. Rice Univ., Houston, TX (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2469-9985; PRVCAN
Grant/Contract Number:
SC0012704; FG-88ER40388; AC02-98CH10886; SC0012185
Accepted Manuscript
Journal Name:
Physical Review C
Additional Journal Information:
Journal Volume: 97; Journal Issue: 2; Journal ID: ISSN 2469-9985
American Physical Society (APS)
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
Country of Publication:
United States
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1420198