2025/09/23 by R. Aaij, LHCb collaboration, A. S. W. Abdelmotteleb +2374 · 2 voices
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #hep-ex
paper · pdf · doi:10.48550/arxiv.2509.18817
arxiv published 2025/09/23 · arxiv updated 2026/04/06
The pp → W± (→ μ± νμ) X cross-sections are measured at a proton-proton centre-of-mass energy √(s) = 5.02 TeV using a dataset corresponding to an integrated luminosity of 100 pb-1 recorded by the LHCb experiment. Considering muons in the pseudorapidity range 2.2 < η< 4.4, the cross-sections are measured differentially in twelve intervals of muon transverse momentum between 28 < pT < 52 GeV. Integrated over pT, the measured cross-sections are σW+ → μ+ νμ = 300.9 ± 2.4 ± 3.8 ± 6.0~pb,
σW- → μ- νμ = 236.9 ± 2.1 ± 2.7 ± 4.7~pb, where the first uncertainties are statistical, the second are systematic, and the third are associated with the luminosity calibration. These integrated results are consistent with theoretical predictions. This analysis introduces a new method to determine the W-boson mass using the measured differential cross-sections corrected for detector effects. The measurement is performed on this statistically limited dataset as a proof of principle and yields mW = 80369 ± 130 ± 33~MeV, where the first uncertainty is experimental and the second is theoretical.