The first measurement of the CP asymmetry of the decay rate (ACP) and the CP average (ΣAFB) and CP asymmetry (ΔAFB) of the forward-backward asymmetry in the muon system of Λþ c → pμþμ− decays is reported. The measurement is performed using a data sample of proton-proton collisions, recorded by the LHCb experiment from 2016 to 2018 at a center-of-mass energy of 13 TeV, which corresponds to an integrated luminosity of 5.4 fb−1. The asymmetries are measured in two regions of dimuon mass near the ϕ-meson mass peak. The dimuon-mass integrated results are ACP ¼ ð−1.1 4.0 0.5Þ%, ΣAFB ¼ ð3.9 4.0 0.6Þ%, ΔAFB ¼ ð3.1 4.0 0.4Þ%, where the first uncertainty is statistical and the second systematic. The results are consistent with the conservation of CP symmetry and the Standard Model expectations.

Search for resonance-enhanced CP and angular asymmetries in the Λc+→pμ+μ− decay at LHCb

De Angelis, C.;Dettori, F.;Fabiano, F.;Manca, G.;Oldeman, R.;Provenzano, D.;Saitta, B.;
2025-01-01

Abstract

The first measurement of the CP asymmetry of the decay rate (ACP) and the CP average (ΣAFB) and CP asymmetry (ΔAFB) of the forward-backward asymmetry in the muon system of Λþ c → pμþμ− decays is reported. The measurement is performed using a data sample of proton-proton collisions, recorded by the LHCb experiment from 2016 to 2018 at a center-of-mass energy of 13 TeV, which corresponds to an integrated luminosity of 5.4 fb−1. The asymmetries are measured in two regions of dimuon mass near the ϕ-meson mass peak. The dimuon-mass integrated results are ACP ¼ ð−1.1 4.0 0.5Þ%, ΣAFB ¼ ð3.9 4.0 0.6Þ%, ΔAFB ¼ ð3.1 4.0 0.4Þ%, where the first uncertainty is statistical and the second systematic. The results are consistent with the conservation of CP symmetry and the Standard Model expectations.
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11584/445358
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