Abstract
The pseudorapidity distributions of dijets as functions of their average transverse momentum () are measured in proton-lead () and proton-proton () collisions. The data samples were collected by the CMS experiment at the CERN LHC, at a nucleon-nucleon center-of-mass energy of 5.02 TeV. A significant modification of the spectra with respect to the spectra is observed in all intervals investigated. The ratios of the and distributions are compared to next-to-leading order perturbative quantum chromodynamics calculations with unbound nucleon and nuclear parton distribution functions (PDFs). These results give the first evidence that the gluon PDF at large Bjorken in lead ions is strongly suppressed with respect to the PDF in unbound nucleons.
- Received 12 May 2018
- Corrected 19 October 2018
DOI:https://doi.org/10.1103/PhysRevLett.121.062002
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.
© 2018 CERN, for the CMS Collaboration
Physics Subject Headings (PhySH)
Corrections
19 October 2018
Correction: Incorrect values of the leading of the jet appeared in the eighth paragraph and in Figs. 2 and 3 and have been corrected. In the affiliations section, U.S. names of states were missing and now have been included.