A measurement of the ratio of branching fractions R(J/psi) = B(B-c(+) -> J/psi tau(+)nu(tau))/B(B-c(+) -> J/psi mu(+)nu(mu)) in the J/psi -> mu(+)mu(-), tau(+) -> mu(+)nu(mu)(nu) over bar (tau) decay channel is presented. This measurement uses a sample of proton-proton collision data collected at a center-of-mass energy of 13 TeV by the CMS experiment in 2018, corresponding to an integrated luminosity of 59.7 fb(-1). The measured ratio, R(J/psi) = 0.17(-0.17)(+0.18) (stat)(+0.21)(-0.22) (syst)(+0.19)(-0.18) (theo) = 0.17 +/- 0.33, agrees with the value of 0.2582 +/- 0.0038 predicted by the standard model, which assumes lepton flavor universality. By testing lepton flavor universality, this measurement is a probe of new physics using B-c(+) mesons, which are currently only produced at the LHC.

Hayrapetyan, A., Tumasyan, A., Adam, W., Andrejkovic, J.W., Bergauer, T., Chatterjee, S., et al. (2025). Test of lepton flavor universality in semileptonic B+c meson decays in proton-proton collisions at √s=13 TeV. PHYSICAL REVIEW D, 111 [10.1103/PhysRevD.111.L051102].

Test of lepton flavor universality in semileptonic B+c meson decays in proton-proton collisions at √s=13 TeV

Ciocci, M. A.;D'Amante, V.;Turini, N.;
2025-01-01

Abstract

A measurement of the ratio of branching fractions R(J/psi) = B(B-c(+) -> J/psi tau(+)nu(tau))/B(B-c(+) -> J/psi mu(+)nu(mu)) in the J/psi -> mu(+)mu(-), tau(+) -> mu(+)nu(mu)(nu) over bar (tau) decay channel is presented. This measurement uses a sample of proton-proton collision data collected at a center-of-mass energy of 13 TeV by the CMS experiment in 2018, corresponding to an integrated luminosity of 59.7 fb(-1). The measured ratio, R(J/psi) = 0.17(-0.17)(+0.18) (stat)(+0.21)(-0.22) (syst)(+0.19)(-0.18) (theo) = 0.17 +/- 0.33, agrees with the value of 0.2582 +/- 0.0038 predicted by the standard model, which assumes lepton flavor universality. By testing lepton flavor universality, this measurement is a probe of new physics using B-c(+) mesons, which are currently only produced at the LHC.
2025
Hayrapetyan, A., Tumasyan, A., Adam, W., Andrejkovic, J.W., Bergauer, T., Chatterjee, S., et al. (2025). Test of lepton flavor universality in semileptonic B+c meson decays in proton-proton collisions at √s=13 TeV. PHYSICAL REVIEW D, 111 [10.1103/PhysRevD.111.L051102].
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11365/1324264
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