The first measurement of the CP asymmetry of the decay rate (A_CP) and the CP average (ΣA_FB) and CP asymmetry (ΔA_FB) of the forward-backward asymmetry in the muon system of Λc+ → p μ+ μ− 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 A_CP = (−1.1 ± 4.0 ± 0.5)%, ΣA_FB = (3.9 ± 4.0 ± 0.6)%, ΔA_FB = (3.1 ± 4.0 ± 0.4)%, 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.

Aaij, R., Abdelmotteleb, A. s. w., Abellan Beteta, C., Abudinén, F., Ackernley, T., Adefisoye, A. a., et al. (2025). Search for resonance-enhanced CP and angular asymmetries in the Λc+ → p μ+ μ− decay at LHCb. PHYSICAL REVIEW D, 111(9), 1-14 [10.1103/physrevd.111.l091102].

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

Carbone, A.;Ferrari, F.;Galli, D.;Patrignani, C.;Spedicato, E.;Villa, A.;Zenesini, F.;
2025

Abstract

The first measurement of the CP asymmetry of the decay rate (A_CP) and the CP average (ΣA_FB) and CP asymmetry (ΔA_FB) of the forward-backward asymmetry in the muon system of Λc+ → p μ+ μ− 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 A_CP = (−1.1 ± 4.0 ± 0.5)%, ΣA_FB = (3.9 ± 4.0 ± 0.6)%, ΔA_FB = (3.1 ± 4.0 ± 0.4)%, 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.
2025
Aaij, R., Abdelmotteleb, A. s. w., Abellan Beteta, C., Abudinén, F., Ackernley, T., Adefisoye, A. a., et al. (2025). Search for resonance-enhanced CP and angular asymmetries in the Λc+ → p μ+ μ− decay at LHCb. PHYSICAL REVIEW D, 111(9), 1-14 [10.1103/physrevd.111.l091102].
Aaij, R.; Abdelmotteleb, A.  s.  w.; Abellan Beteta, C.; Abudinén, F.; Ackernley, T.; Adefisoye, A.  a.; Adeva, B.; Adinolfi, M.; Adlarson, P.; Agapop...espandi
File in questo prodotto:
File Dimensione Formato  
2025-AR-24-Sea_for_Reson_Enhanc_CP_and_Angular_Asymms-PRD.pdf

accesso aperto

Tipo: Versione (PDF) editoriale / Version Of Record
Licenza: Licenza per Accesso Aperto. Creative Commons Attribuzione (CCBY)
Dimensione 735.91 kB
Formato Adobe PDF
735.91 kB Adobe PDF Visualizza/Apri
supplemental (2).pdf

accesso aperto

Tipo: File Supplementare
Licenza: Licenza per Accesso Aperto. Creative Commons Attribuzione (CCBY)
Dimensione 193.23 kB
Formato Adobe PDF
193.23 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/1035074
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
  • ???jsp.display-item.citation.isi??? 1
social impact