The production of W-+/- bosons is studied in proton-lead (pPb)collisions at a nucleon-nucleon centre-of-mass energy of root s(NN) =8.16 TeV. Measurements are performed in the W-+/- -> mu(+/-)nu(mu)channel using a data sample corresponding to an integrated luminosity of173.4 +/- 6.1 nb(-1), collected by the CMS Collaboration at the LHC. Thenumber of positively and negatively charged W bosons is determinedseparately in the muon pseudorapidity region in the laboratory framevertical bar eta(mu)(lab)vertical bar < 2.4 and transverse momentump(T)(mu) > 25 GeV/c. The W-+/- boson differential cross sections, muoncharge asymmetry, and the ratios of W-+/- boson yields for theproton-going over the Pb-going beam directions are reported as afunction of the muon pseudorapidity in the nucleon-nucleoncentre-of-mass frame. The measurements are compared to the predictionsfrom theoretical calculations based on parton distribution functions(PDFs) at next-to-leading-order. The results favour PDF calculationsthat include nuclear modifications and provide constraints on thenuclear PDF global fits. (C) 2019 The Author(s). Published by ElsevierB.V.
Observation of nuclear modifications in W-+/- boson production in pPb collisions at root s(NN)=8.16 TeV
Albergo, S.;Potenza, R.;Tricomi, A.;Tuve, C.;
2020-01-01
Abstract
The production of W-+/- bosons is studied in proton-lead (pPb)collisions at a nucleon-nucleon centre-of-mass energy of root s(NN) =8.16 TeV. Measurements are performed in the W-+/- -> mu(+/-)nu(mu)channel using a data sample corresponding to an integrated luminosity of173.4 +/- 6.1 nb(-1), collected by the CMS Collaboration at the LHC. Thenumber of positively and negatively charged W bosons is determinedseparately in the muon pseudorapidity region in the laboratory framevertical bar eta(mu)(lab)vertical bar < 2.4 and transverse momentump(T)(mu) > 25 GeV/c. The W-+/- boson differential cross sections, muoncharge asymmetry, and the ratios of W-+/- boson yields for theproton-going over the Pb-going beam directions are reported as afunction of the muon pseudorapidity in the nucleon-nucleoncentre-of-mass frame. The measurements are compared to the predictionsfrom theoretical calculations based on parton distribution functions(PDFs) at next-to-leading-order. The results favour PDF calculationsthat include nuclear modifications and provide constraints on thenuclear PDF global fits. (C) 2019 The Author(s). Published by ElsevierB.V.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
