The study of the Cabibbo-favored semileptonic decay Λ+c → Λμ+νμ is reported using 4.5 fb−1 of e+e− annihilation data collected at center-of-mass energies ranging from 4.600 to 4.699 GeV. The branching fraction of the decay is measured to be B(Λ+c → Λμ+νμ) = (3.48 pm 0.14stat pm 0.10syst)%, 3 times more precise than the prior world average result. Tests of lepton flavor universality using Λ+c → Λl+νl (l = e, μ) decays are reported for the first time, based on measurements of the differential decay rates and the forward-backward asymmetries in separate four-momentum transfer regions. The results are compatible with Standard Model predictions. Furthermore, we improve the determination of the form-factor parameters in Λ+c → Λl+νl decays, which provide stringent tests and calibration for lattice quantum chromodynamics calculations.

Study of Λc+→Λμ+νμ and test of lepton flavor universality with Λc+→Λℓ+νℓ decays

Garzia, I.;Gramigna, S.;
2023

Abstract

The study of the Cabibbo-favored semileptonic decay Λ+c → Λμ+νμ is reported using 4.5 fb−1 of e+e− annihilation data collected at center-of-mass energies ranging from 4.600 to 4.699 GeV. The branching fraction of the decay is measured to be B(Λ+c → Λμ+νμ) = (3.48 pm 0.14stat pm 0.10syst)%, 3 times more precise than the prior world average result. Tests of lepton flavor universality using Λ+c → Λl+νl (l = e, μ) decays are reported for the first time, based on measurements of the differential decay rates and the forward-backward asymmetries in separate four-momentum transfer regions. The results are compatible with Standard Model predictions. Furthermore, we improve the determination of the form-factor parameters in Λ+c → Λl+νl decays, which provide stringent tests and calibration for lattice quantum chromodynamics calculations.
2023
Ablikim, M.; Achasov, M.  N.; Adlarson, P.; Ai, X.  C.; Aliberti, R.; Amoroso, A.; An, M.  R.; An, Q.; Bai, Y.; Bakina, O.; Balossino, I.; Ban, Y.; Ba...espandi
File in questo prodotto:
File Dimensione Formato  
PhysRevD.108.L031105.pdf

accesso aperto

Descrizione: Full text editoriale
Tipologia: Full text (versione editoriale)
Licenza: Creative commons
Dimensione 626.72 kB
Formato Adobe PDF
626.72 kB Adobe PDF Visualizza/Apri

I documenti in SFERA 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/11392/2530506
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 9
  • ???jsp.display-item.citation.isi??? 2
social impact