Additional spin-0 particles appear in many extensions of the standard model. We search for long-lived spin-0 particles S in B-meson decays mediated by a b→s quark transition in e+e− collisions at the Υ(4S) resonance at the Belle II experiment. Based on a sample corresponding to an integrated luminosity of 189 fb−1, we observe no evidence for signal. We set model-independent upper limits on the product of branching fractions B(B0→K∗(892)0(→K+π−)S)×B(S→x+x−) and B(B+→K+S)×B(S→x+x−), where x+x− indicates e+e−,μ+μ−,π+π−, or K+K−, as functions of S mass and lifetime at the level of 10−7.
Adachi, I., Adamczyk, K., Aggarwal, L., Aihara, H., Akopov, N., Aloisio, A., et al. (2023). Search for a long-lived spin-0 mediator in b→s transitions at the Belle II experiment. PHYSICAL REVIEW D, 108(11), L111104-1-L111104-7 [10.1103/PhysRevD.108.L111104].
Search for a long-lived spin-0 mediator in b→s transitions at the Belle II experiment
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
;
2023-01-01
Abstract
Additional spin-0 particles appear in many extensions of the standard model. We search for long-lived spin-0 particles S in B-meson decays mediated by a b→s quark transition in e+e− collisions at the Υ(4S) resonance at the Belle II experiment. Based on a sample corresponding to an integrated luminosity of 189 fb−1, we observe no evidence for signal. We set model-independent upper limits on the product of branching fractions B(B0→K∗(892)0(→K+π−)S)×B(S→x+x−) and B(B+→K+S)×B(S→x+x−), where x+x− indicates e+e−,μ+μ−,π+π−, or K+K−, as functions of S mass and lifetime at the level of 10−7.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
