A measurement of the time-dependent CP-violating asymmetry in B0s → ϕ ϕ decays is presented. Using a sample of proton-proton collision data corresponding to an integrated luminosity of 5.0 fb^−1 collected by the LHCb experiment at centre-of-mass energies √s = 7 TeV in 2011, 8 TeV in 2012 and 13 TeV in 2015 and 2016, a signal yield of around 9000 B0s → ϕ ϕ decays is obtained. The CP-violating phase ϕ_{s}^{s anti-s s} is measured to be −0.073 ± 0.115 (stat) ± 0.027 (syst) rad, under the assumption it is independent of the helicity of the ϕ ϕ decay. In addition, the CP-violating phases of the transverse polarisations under the assumption of CP conservation of the longitudinal phase are measured. The helicity-independent direct CP-violation parameter is also measured, and is found to be |λ| = 0.99 ± 0.05 (stat) ± 0.01 (syst). In addition, T-odd triple-product asymmetries are measured. The results obtained are consistent with the hypothesis of CP conservation in anti-b → anti-s s anti-s s transitions. Finally, a limit on the branching fraction of the B0 → ϕ ϕ decay is determined to be B(B0 → ϕ ϕ) < 2.7 × 10^−8 at 90% confidence level.

Aaij, R., Abellán Beteta, C., Adeva, B., Adinolfi, M., Aidala, C.A., Ajaltouni, Z., et al. (2019). Measurement of CP Violation in the B0s → ϕ ϕ Decay and Search for the B0 → ϕ ϕ Decay. JOURNAL OF HIGH ENERGY PHYSICS, 2019(12), 0-32 [10.1007/JHEP12(2019)155].

Measurement of CP Violation in the B0s → ϕ ϕ Decay and Search for the B0 → ϕ ϕ Decay

Betti, F.;Capriotti, L.;Carbone, A.;Ferrari, F.;Galli, D.;Gioventù, A.;Patrignani, C.;Perazzini, S.;Pisani, F.;Vagnoni, V.;Zucchelli, S.
2019

Abstract

A measurement of the time-dependent CP-violating asymmetry in B0s → ϕ ϕ decays is presented. Using a sample of proton-proton collision data corresponding to an integrated luminosity of 5.0 fb^−1 collected by the LHCb experiment at centre-of-mass energies √s = 7 TeV in 2011, 8 TeV in 2012 and 13 TeV in 2015 and 2016, a signal yield of around 9000 B0s → ϕ ϕ decays is obtained. The CP-violating phase ϕ_{s}^{s anti-s s} is measured to be −0.073 ± 0.115 (stat) ± 0.027 (syst) rad, under the assumption it is independent of the helicity of the ϕ ϕ decay. In addition, the CP-violating phases of the transverse polarisations under the assumption of CP conservation of the longitudinal phase are measured. The helicity-independent direct CP-violation parameter is also measured, and is found to be |λ| = 0.99 ± 0.05 (stat) ± 0.01 (syst). In addition, T-odd triple-product asymmetries are measured. The results obtained are consistent with the hypothesis of CP conservation in anti-b → anti-s s anti-s s transitions. Finally, a limit on the branching fraction of the B0 → ϕ ϕ decay is determined to be B(B0 → ϕ ϕ) < 2.7 × 10^−8 at 90% confidence level.
2019
Aaij, R., Abellán Beteta, C., Adeva, B., Adinolfi, M., Aidala, C.A., Ajaltouni, Z., et al. (2019). Measurement of CP Violation in the B0s → ϕ ϕ Decay and Search for the B0 → ϕ ϕ Decay. JOURNAL OF HIGH ENERGY PHYSICS, 2019(12), 0-32 [10.1007/JHEP12(2019)155].
Aaij, R.; Abellán Beteta, C.; Adeva, B.; Adinolfi, M.; Aidala, C. A.; Ajaltouni, Z.; Akar, S.; Albicocco, P.; Albrecht, J.; Alessio, F.; Alexander, M....espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/720619
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