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Title: Study of jet quenching with Z+jet correlations in PbPb and pp collisions at $$\sqrt{s_{NN}}$$ = 5.02 TeV

Abstract

The production of jets in association with Z bosons, reconstructed via the mu+mu- and e+e- decay channels, is studied in pp and, for the first time, in PbPb collisions. Both data samples were collected by the CMS experiment at the LHC, at a center-of-mass energy of 5.02 TeV. The PbPb collisions were analyzed in the 0-30% centrality range. The back-to-back azimuthal alignment was studied in both pp and PbPb collisions for Z bosons with transverse momentum ptz > 60 GeV/c and a recoiling jet with ptj > 30 GeV/c. The pt imbalance, xjz= ptj/ptz, as well as the average number of jet partners per Z, rjz, were studied in intervals of ptz, in both pp and PbPb collisions. The rjz is found to be smaller in PbPb than in pp collisions, which suggests that in PbPb collisions a larger fraction of partons, associated with the Z bosons, lose energy and fall below the 30 GeV/c ptj threshold.

Authors:
;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Org.:
CMS
OSTI Identifier:
1352040
Report Number(s):
FERMILAB-PUB-17-116-CMS; CMS-HIN-15-013; CERN-EP-2017-002; arXiv:1702.01060
1512112
DOE Contract Number:
AC02-07CH11359
Resource Type:
Journal Article
Resource Relation:
Journal Name: TBD
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Sirunyan, Albert M, and et al. Study of jet quenching with Z+jet correlations in PbPb and pp collisions at $\sqrt{s_{NN}}$ = 5.02 TeV. United States: N. p., 2017. Web.
Sirunyan, Albert M, & et al. Study of jet quenching with Z+jet correlations in PbPb and pp collisions at $\sqrt{s_{NN}}$ = 5.02 TeV. United States.
Sirunyan, Albert M, and et al. Fri . "Study of jet quenching with Z+jet correlations in PbPb and pp collisions at $\sqrt{s_{NN}}$ = 5.02 TeV". United States. doi:. https://www.osti.gov/servlets/purl/1352040.
@article{osti_1352040,
title = {Study of jet quenching with Z+jet correlations in PbPb and pp collisions at $\sqrt{s_{NN}}$ = 5.02 TeV},
author = {Sirunyan, Albert M and et al.},
abstractNote = {The production of jets in association with Z bosons, reconstructed via the mu+mu- and e+e- decay channels, is studied in pp and, for the first time, in PbPb collisions. Both data samples were collected by the CMS experiment at the LHC, at a center-of-mass energy of 5.02 TeV. The PbPb collisions were analyzed in the 0-30% centrality range. The back-to-back azimuthal alignment was studied in both pp and PbPb collisions for Z bosons with transverse momentum ptz > 60 GeV/c and a recoiling jet with ptj > 30 GeV/c. The pt imbalance, xjz= ptj/ptz, as well as the average number of jet partners per Z, rjz, were studied in intervals of ptz, in both pp and PbPb collisions. The rjz is found to be smaller in PbPb than in pp collisions, which suggests that in PbPb collisions a larger fraction of partons, associated with the Z bosons, lose energy and fall below the 30 GeV/c ptj threshold.},
doi = {},
journal = {TBD},
number = ,
volume = ,
place = {United States},
year = {Fri Feb 03 00:00:00 EST 2017},
month = {Fri Feb 03 00:00:00 EST 2017}
}
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