T -odd asymmetry in W+ jet events at the LHC

Summary, in English

W bosons produced at high transverse momentum in hadron collisions can have polarization along the direction perpendicular to the production plane, which is odd under naïve T reversal where both the three-momenta and angular momenta are reversed. Perturbative QCD predicts nonzero polarization at the one-loop level, which can be measured as parity-odd components in the angular distribution of charged leptons from the decay of W bosons. We perform a detector-level simulation with the generator MadGraph5-aMC@NLO, and demonstrate that the asymmetry can be observed at the 8 TeV LHC with 20fb-1 of data. If confirmed, it will be the first experimental measurement of the sign of the imaginary part of one-loop QCD amplitudes.

• Author: Rikkert Frederix; Kaoru Hagiwara; Toshifumi Yamada; Hiroshi Yokoya
• Publishing year: 2014-10-06
• Language: English
• Publication/Series: Physical Review Letters
• Volume: 113
• Issue: 15
• Links: http://dx.doi.org/10.1103/PhysRevLett.113.152001
• Document type: Journal article
• Publisher: American Physical Society
• Topic: Subatomic Physics
• Status: Published
• ISBN/ISSN/Other: ISSN: 0031-9007