The first observation of Z boson production in proton-lead collisions at a centre-of-mass energy per proton-nucleon pair of √sNN = 5TeV is presented. The data sample corresponds to an integrated luminosity of 1.6 nb −1collected with the LHCb detector. The Z candidates are reconstructed from pairs of oppositely charged muons with pseudorapidities between 2.0 and 4.5 and transverse momenta above 20 GeV/c. The invariant dimuon mass is restricted to the range 60−120 GeV/c. The Z production cross-section is measured to be in the direction of the proton beam and in the direction of the lead beam, where the first uncertainty is statistical and the second systematic.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics