An angular analysis of the B0s → ϕ e+ e− decay is performed using the proton-proton collision dataset collected between 2011 and 2018 by the LHCb experiment, corresponding to an integrated luminosity of 9 fb^−1 at centre-of-mass energies of 7, 8 and 13 TeV. The analysis is performed in the very low dielectron invariant mass-squared region between 0.0009 and 0.2615 GeV^2/c^4. The longitudinal polarisation fraction of the ϕ meson is measured to be less than 11.5% at 90% confidence level. The A_T^ReCP observable, which is related to the lepton forward-backward asymmetry, is measured to be 0.116 ± 0.155 ± 0.006, where the first uncertainty is statistical and the second systematic. The transverse asymmetries, A_T^(2) and A_T^ImCP, which are sensitive to the virtual photon polarisation, are found to be −0.045 ± 0.235 ± 0.014 and 0.002 ± 0.247 ± 0.016, respectively. The results are consistent with Standard Model predictions.

Aaij, R., Abdelmotteleb, A.S.W., Abellan Beteta, C., Abudinén, F., Ackernley, T., Adefisoye, A.A., et al. (2025). Constraints on the photon polarisation in b → s γ transitions using B0s → ϕ e+ e− decays. JOURNAL OF HIGH ENERGY PHYSICS, 2025(3), 0-22 [10.1007/jhep03(2025)047].

Constraints on the photon polarisation in b → s γ transitions using B0s → ϕ e+ e− decays

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

Abstract

An angular analysis of the B0s → ϕ e+ e− decay is performed using the proton-proton collision dataset collected between 2011 and 2018 by the LHCb experiment, corresponding to an integrated luminosity of 9 fb^−1 at centre-of-mass energies of 7, 8 and 13 TeV. The analysis is performed in the very low dielectron invariant mass-squared region between 0.0009 and 0.2615 GeV^2/c^4. The longitudinal polarisation fraction of the ϕ meson is measured to be less than 11.5% at 90% confidence level. The A_T^ReCP observable, which is related to the lepton forward-backward asymmetry, is measured to be 0.116 ± 0.155 ± 0.006, where the first uncertainty is statistical and the second systematic. The transverse asymmetries, A_T^(2) and A_T^ImCP, which are sensitive to the virtual photon polarisation, are found to be −0.045 ± 0.235 ± 0.014 and 0.002 ± 0.247 ± 0.016, respectively. The results are consistent with Standard Model predictions.
2025
Aaij, R., Abdelmotteleb, A.S.W., Abellan Beteta, C., Abudinén, F., Ackernley, T., Adefisoye, A.A., et al. (2025). Constraints on the photon polarisation in b → s γ transitions using B0s → ϕ e+ e− decays. JOURNAL OF HIGH ENERGY PHYSICS, 2025(3), 0-22 [10.1007/jhep03(2025)047].
Aaij, R.; Abdelmotteleb, A. S. W.; Abellan Beteta, C.; Abudinén, F.; Ackernley, T.; Adefisoye, A. A.; Adeva, B.; Adinolfi, M.; Adlarson, P.; Agapopoul...espandi
File in questo prodotto:
Eventuali allegati, non sono esposti

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/11585/1007370
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact