The first observation of the suppressed semileptonic Bs0→K-μ+νμ decay is reported. Using a data sample recorded in pp collisions in 2012 with the LHCb detector, corresponding to an integrated luminosity of 2 fb-1, the branching fraction B(Bs0→K-μ+νμ) is measured to be [1.06±0.05(stat)±0.08(syst)]×10-4, where the first uncertainty is statistical and the second one represents the combined systematic uncertainties. The decay Bs0→Ds-μ+νμ, where Ds- is reconstructed in the final state K+K-π-, is used as a normalization channel to minimize the experimental systematic uncertainty. Theoretical calculations on the form factors of the Bs0→K- and Bs0→Ds- transitions are employed to determine the ratio of the Cabibbo-Kobayashi-Maskawa matrix elements |Vub|/|Vcb| at low and high Bs0→K- momentum transfer.

First Observation of the Decay Bs0 →K-μ+νμ and a Measurement of |Vub | / |Vcb |

Calabrese R.;Capriotti L.;Couturier B.;Fiorini M.;Franzoso E.;Giugliano C.;Guarise M.;Kotriakhova S.;Luppi E.;Neri I.;Pappalardo L. L.;Passalacqua B.;Siddi B. G.;Tomassetti L.;
2021

Abstract

The first observation of the suppressed semileptonic Bs0→K-μ+νμ decay is reported. Using a data sample recorded in pp collisions in 2012 with the LHCb detector, corresponding to an integrated luminosity of 2 fb-1, the branching fraction B(Bs0→K-μ+νμ) is measured to be [1.06±0.05(stat)±0.08(syst)]×10-4, where the first uncertainty is statistical and the second one represents the combined systematic uncertainties. The decay Bs0→Ds-μ+νμ, where Ds- is reconstructed in the final state K+K-π-, is used as a normalization channel to minimize the experimental systematic uncertainty. Theoretical calculations on the form factors of the Bs0→K- and Bs0→Ds- transitions are employed to determine the ratio of the Cabibbo-Kobayashi-Maskawa matrix elements |Vub|/|Vcb| at low and high Bs0→K- momentum transfer.
2021
Aaij, R.; Abellan Beteta, C.; Ackernley, T.; Adeva, B.; Adinolfi, M.; Afsharnia, H.; Aidala, C. A.; Aiola, S.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; ...espandi
File in questo prodotto:
File Dimensione Formato  
PhysRevLett.126.081804.pdf

accesso aperto

Descrizione: Full text editoriale
Tipologia: Full text (versione editoriale)
Licenza: Creative commons
Dimensione 331 kB
Formato Adobe PDF
331 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/11392/2476444
Citazioni
  • ???jsp.display-item.citation.pmc??? 1
  • Scopus 50
  • ???jsp.display-item.citation.isi??? 23
social impact