Research output: Contribution to journal › Article › peer-review
Observation of a Λb0 − Λ¯b0 production asymmetry in proton-proton collisions at √s = 7 and 8 TeV. / The LHCb Collaboration.
In: Journal of High Energy Physics, Vol. 2021, No. 10, 60, 10.2021.Research output: Contribution to journal › Article › peer-review
}
TY - JOUR
T1 - Observation of a Λb0 − Λ¯b0 production asymmetry in proton-proton collisions at √s = 7 and 8 TeV
AU - The LHCb Collaboration
AU - Aaij, R.
AU - Abdelmotteleb, A. S.W.
AU - Abellán Beteta, C.
AU - Ackernley, T.
AU - Adeva, B.
AU - Adinolfi, M.
AU - Afsharnia, H.
AU - Aidala, C. A.
AU - Aiola, S.
AU - Ajaltouni, Z.
AU - Akar, S.
AU - Albrecht, J.
AU - Alessio, F.
AU - Alexander, M.
AU - Alfonso Albero, A.
AU - Aliouche, Z.
AU - Alkhazov, G.
AU - Alvarez Cartelle, P.
AU - Amato, S.
AU - Amey, J. L.
AU - Amhis, Y.
AU - An, L.
AU - Anderlini, L.
AU - Andreianov, A.
AU - Andreotti, M.
AU - Archilli, F.
AU - Artamonov, A.
AU - Artuso, M.
AU - Arzymatov, K.
AU - Aslanides, E.
AU - Atzeni, M.
AU - Audurier, B.
AU - Bachmann, S.
AU - Bachmayer, M.
AU - Back, J. J.
AU - Baladron Rodriguez, P.
AU - Balagura, V.
AU - Baldini, W.
AU - Baptista Leite, J.
AU - Barlow, R. J.
AU - Barsuk, S.
AU - Barter, W.
AU - Bartolini, M.
AU - Bondar, A.
AU - Eidelman, S.
AU - Krokovny, P.
AU - Kudryavtsev, V.
AU - Maltsev, T.
AU - Shekhtman, L.
AU - Vorobyev, V.
N1 - Publisher Copyright: © 2021, The Author(s).
PY - 2021/10
Y1 - 2021/10
N2 - 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.
AB - 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.
KW - B physics
KW - Hadron-Hadron scattering (experiments)
KW - Hard scattering
KW - Heavy quark production
KW - proton-proton scattering
UR - http://www.scopus.com/inward/record.url?scp=85117519560&partnerID=8YFLogxK
U2 - 10.1007/JHEP10(2021)060
DO - 10.1007/JHEP10(2021)060
M3 - Article
AN - SCOPUS:85117519560
VL - 2021
JO - Journal of High Energy Physics
JF - Journal of High Energy Physics
SN - 1029-8479
IS - 10
M1 - 60
ER -
ID: 34538993