%0 Journal Article
%T Observation of a Lambda(0)(b) – (Lambda)over-bar(b)(0) production asymmetry in proton-proton collisions at root s=7 and 8 TeV
%A LHCb Collaboration (Aaij, R. et al
%A Jashal, B. K.
%A Martinez-Vidal, F.
%A Oyanguren, A.
%A Remon Alepuz, C.
%A Ruiz Vidal, J.
%J Journal of High Energy Physics
%D 2021
%V 10
%N 10
%I Springer
%@ 1029-8479
%G English
%F LHCbCollaborationAaij_etal2021
%O WOS:000705235400002
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=4985), last updated on Sun, 24 Oct 2021 17:49:45 +0000
%X This article presents differential measurements of the asymmetry between Lambda(0)(b) and (Lambda) over bar (0)(b) baryon production rates in proton-proton collisions at centre-of-mass energies of root s = 7 and 8 TeV collected with the LHCb experiment, corresponding to an integrated luminosity of 3 fb(-1). The Lambda(0)(b) baryons are reconstructed through the inclusive semileptonic decay Lambda(0)(b) -> Lambda(+)(c) mu(-)(nu) over bar X-mu. The production asymmetry is measured both in intervals of rapidity in the range 2:15 < y < 4:10 and transverse momentum in 2 < p T < 27 GeV/c. The results are found to be incompatible with symmetric production with a significance of 5.8 standard deviations for both root 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.
%K Hadron-Hadron scattering (experiments)
%K Heavy quark production
%K proton-proton scattering
%K Hard scattering
%K B physics
%R 10.1007/JHEP10(2021)060
%U https://arxiv.org/abs/2107.09593
%U https://doi.org/10.1007/JHEP10(2021)060
%P 060-38pp