Observation of Nuclear Modifications in W± Boson Production in pPb Collisions at √sNN = 8.16 TeV
Physics Letters B 2020
Viesturs Veckalns

The production of W± bosons is studied in proton-lead (pPb) collisions at a nucleon-nucleon centre-of-mass energy of sNN=8.16TeV. Measurements are performed in the W±→μ±νμ channel using a data sample corresponding to an integrated luminosity of 173.4±6.1nb−1, collected by the CMS Collaboration at the LHC. The number of positively and negatively charged W bosons is determined separately in the muon pseudorapidity region in the laboratory frame |ηlabμ|<2.4 and transverse momentum pTμ>25GeV/c. The W± boson differential cross sections, muon charge asymmetry, and the ratios of W± boson yields for the proton-going over the Pb-going beam directions are reported as a function of the muon pseudorapidity in the nucleon-nucleon centre-of-mass frame. The measurements are compared to the predictions from theoretical calculations based on parton distribution functions (PDFs) at next-to-leading-order. The results favour PDF calculations that include nuclear modifications and provide constraints on the nuclear PDF global fits.


Keywords
CMS | Electroweak | Heavy ions | nPDF | pPb | W boson
DOI
10.1016/j.physletb.2019.135048
Hyperlink
https://www.sciencedirect.com/science/article/pii/S0370269319307701?via%3Dihub

Veckalns, V., CERN international group of authors. Observation of Nuclear Modifications in W± Boson Production in pPb Collisions at √sNN = 8.16 TeV. Physics Letters B, 2020, Vol. 800, Article number 135048. ISSN 0370-2693. Available from: doi:10.1016/j.physletb.2019.135048

Publication language
English (en)
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