We present a search for the rare flavor-changing neutral-current decay B0→K∗0τ+τ- with data collected by the Belle II experiment at the SuperKEKB electron-positron collider. The analysis uses a 365 fb-1 data sample recorded at the center-of-mass energy of the ϒ(4S) resonance. One of the B mesons produced in the ϒ(4S)→B0B¯0 process is fully reconstructed in a hadronic decay mode, while its companion B meson is required to decay into a K∗0 and two τ leptons of opposite charge. The τ leptons are reconstructed in final states with a single electron, muon, charged pion or charged ρ meson, and additional neutrinos. We set an upper limit on the branching fraction of B(B0→K∗0τ+τ-)<1.8×10-3 at the 90% confidence level, which is the most stringent constraint reported to date.

Search for B0 →k∗0τ+τ- Decays at the Belle II Experiment / Adachi, I., Adamczyk, K., Aggarwal, L., Ahmed, H., Aihara, H., Akopov, N., Alhakami, M., Aloisio, A., Althubiti, N., Angelsmark, M., Anh Ky, N., Asner, D.M., Atmacan, H., Aushev, V., Aversano, M., Ayad, R., Babu, V., Bae, H., Baghel, N.K., Bahinipati, S., et al.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 135:15(2025). [10.1103/v1q3-9dy8]

Search for B0 →k∗0τ+τ- Decays at the Belle II Experiment

Aloisio A.;Campajola M.;De Nardo G.;Di Capua F.;Gaudino G.;Giordano R.;Merola M.;Mirra M.;
2025

Abstract

We present a search for the rare flavor-changing neutral-current decay B0→K∗0τ+τ- with data collected by the Belle II experiment at the SuperKEKB electron-positron collider. The analysis uses a 365 fb-1 data sample recorded at the center-of-mass energy of the ϒ(4S) resonance. One of the B mesons produced in the ϒ(4S)→B0B¯0 process is fully reconstructed in a hadronic decay mode, while its companion B meson is required to decay into a K∗0 and two τ leptons of opposite charge. The τ leptons are reconstructed in final states with a single electron, muon, charged pion or charged ρ meson, and additional neutrinos. We set an upper limit on the branching fraction of B(B0→K∗0τ+τ-)<1.8×10-3 at the 90% confidence level, which is the most stringent constraint reported to date.
2025
Search for B0 →k∗0τ+τ- Decays at the Belle II Experiment / Adachi, I., Adamczyk, K., Aggarwal, L., Ahmed, H., Aihara, H., Akopov, N., Alhakami, M., Aloisio, A., Althubiti, N., Angelsmark, M., Anh Ky, N., Asner, D.M., Atmacan, H., Aushev, V., Aversano, M., Ayad, R., Babu, V., Bae, H., Baghel, N.K., Bahinipati, S., et al.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 135:15(2025). [10.1103/v1q3-9dy8]
File in questo prodotto:
Non ci sono file associati a questo prodotto.

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/11588/1043103
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 4
  • ???jsp.display-item.citation.isi??? 2
social impact