The first test of lepton flavor universality between muons and electrons using B+→K+π+π-ℓ+ℓ- (ℓ=e, μ) decays is presented. The measurement is performed with data from proton-proton collisions collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb-1. The ratio of branching fractions between B+→K+π+π-e+e- and B+→K+π+π-μ+μ- decays is measured in the dilepton invariant-mass-squared range 1.1<7.0 GeV2/c4 and is found to be RKππ-1=1.31-0.17+0.18(stat) -0.09+0.12(syst), in agreement with the standard model prediction. The first observation of the B+→K+π+π-e+e- decay is also reported.

Test of Lepton Flavor Universality with B+ →k+π+π-ℓ+ℓ- Decays

Graverini E.;Lazzari F.;Punzi G.;
2025-01-01

Abstract

The first test of lepton flavor universality between muons and electrons using B+→K+π+π-ℓ+ℓ- (ℓ=e, μ) decays is presented. The measurement is performed with data from proton-proton collisions collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb-1. The ratio of branching fractions between B+→K+π+π-e+e- and B+→K+π+π-μ+μ- decays is measured in the dilepton invariant-mass-squared range 1.1<7.0 GeV2/c4 and is found to be RKππ-1=1.31-0.17+0.18(stat) -0.09+0.12(syst), in agreement with the standard model prediction. The first observation of the B+→K+π+π-e+e- decay is also reported.
2025
Aaij, R.; Abdelmotteleb, A. S. W.; Abellan Beteta, C.; Abudinen, F.; Ackernley, T.; Adefisoye, A. A.; Adeva, B.; Adinolfi, M.; Adlarson, P.; Agapopoul...espandi
File in questo prodotto:
File Dimensione Formato  
PhysRevLett.134.181803.pdf

accesso aperto

Tipologia: Versione finale editoriale
Licenza: Creative commons
Dimensione 782.88 kB
Formato Adobe PDF
782.88 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/11568/1312568
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? ND
social impact