Abstract
This article presents differential measurements of the asymmetry between Λb0 and Λ¯b0 baryon production rates in proton-proton collisions at centre-of-mass energies of s = 7 and 8 TeV collected with the LHCb experiment, corresponding to an integrated luminosity of 3 fb−1. The Λb0 baryons are reconstructed through the inclusive semileptonic decay Λb0 → Λc+μ−ν¯ μX. The production asymmetry is measured both in intervals of rapidity in the range 2.15 < y < 4.10 and transverse momentum in 2 < pT< 27 GeV/c. The results are found to be incompatible with symmetric production with a significance of 5.8 standard deviations for both s = 7 and 8 TeV data, assuming no CP violation in the decay. There is evidence for a trend as a function of rapidity with a significance of 4 standard deviations. Comparisons to predictions from hadronisation models in Pythia and heavy-quark recombination are provided. This result constitutes the first observation of a particle-antiparticle asymmetry in b-hadron production at LHC energies. [Figure not available: see fulltext.]
Original language | English (US) |
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Article number | 60 |
Journal | Journal of High Energy Physics |
Volume | 2021 |
Issue number | 10 |
DOIs | |
State | Published - Oct 2021 |
Keywords
- B physics
- Hadron-Hadron scattering (experiments)
- Hard scattering
- Heavy quark production
- proton-proton scattering
ASJC Scopus subject areas
- Nuclear and High Energy Physics