We describe a measurement of charge-parity (CP) violation asymmetries in B0→η′KS0 decays using Belle II data. We consider η′→η(→γγ)π+π- and η′→ρ(→π+π-)γ decays. The data were collected at the SuperKEKB asymmetric-energy e+e- collider between the years 2019 and 2022, and contain (387±6)×106 bottom-antibottom meson pairs. We reconstruct 829±35 signal decays and extract the CP violating parameters from a fit to the distribution of the proper-decay-time difference between the two B mesons. The measured direct and mixing-induced CP asymmetries are Cη′KS0=-0.19±0.08±0.03 and Sη′KS0=+0.67±0.10±0.03, respectively, where the first uncertainties are statistical and the second are systematic. These results are in agreement with current world averages and standard model predictions.
Adachi, I., Aggarwal, L., Ahmed, H., Aihara, H., Akopov, N., Aloisio, A., et al. (2024). Measurement of CP asymmetries in B0→η′KS0 decays at Belle II. PHYSICAL REVIEW D, 110(11), 112002-1-112002-12 [10.1103/physrevd.110.112002].
Measurement of CP asymmetries in B0→η′KS0 decays at Belle II
Branchini, P.Membro del Collaboration Group
;Budano, A.Membro del Collaboration Group
;Bussino, S.Membro del Collaboration Group
;De Pietro, G.Membro del Collaboration Group
;Laurenza, M.Membro del Collaboration Group
;Martellini, C.Membro del Collaboration Group
;Martini, A.Membro del Collaboration Group
;
2024-01-01
Abstract
We describe a measurement of charge-parity (CP) violation asymmetries in B0→η′KS0 decays using Belle II data. We consider η′→η(→γγ)π+π- and η′→ρ(→π+π-)γ decays. The data were collected at the SuperKEKB asymmetric-energy e+e- collider between the years 2019 and 2022, and contain (387±6)×106 bottom-antibottom meson pairs. We reconstruct 829±35 signal decays and extract the CP violating parameters from a fit to the distribution of the proper-decay-time difference between the two B mesons. The measured direct and mixing-induced CP asymmetries are Cη′KS0=-0.19±0.08±0.03 and Sη′KS0=+0.67±0.10±0.03, respectively, where the first uncertainties are statistical and the second are systematic. These results are in agreement with current world averages and standard model predictions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.