Journal article
Observation of X(3872)→J/ψγ and search for X(3872)→ψ′γ in B decays
V Bhardwaj, K Trabelsi, JB Singh, SK Choi, SL Olsen, I Adachi, K Adamczyk, DM Asner, V Aulchenko, T Aushev, T Aziz, AM Bakich, E Barberio, K Belous, B Bhuyan, M Bischofberger, A Bondar, M Bračko, J Brodzicka, TE Browder Show all
Physical Review Letters | Published : 2011
Abstract
We report a study of B→(J/ψγ)K and B→(ψ ′γ)K decay modes using 772×106 BB̄ events collected at the Υ(4S) resonance with the Belle detector at the KEKB energy-asymmetric e+e- collider. We observe X(3872)→J/ψγ and report the first evidence for χc2→J/ψγ in B→(Xcc̄γ)K decays, while in a search for X(3872)→ψ′γ no significant signal is found. We measure the branching fractions, B(B ±→X(3872)K±)B(X(3872)→J/ ψγ)=(1.78-0.44+0.48±0.12)×10-6, B(B ±→χc2K±)=(1.11-0.34+0. 36±0.09)×10-5, B(B±→X(3872)K ±)B(X(3872)→ψ′γ)<3. 45×10-6 (upper limit at 90% C.L.), and also provide upper limits for other searches. © 2011 American Physical Society.
Grants
Awarded by Japan Society for the Promotion of Science
Funding Acknowledgements
We thank the KEKB group for excellent operation of the accelerator, the KEK cryogenics group for efficient solenoid operations, and the KEK computer group and the NII for valuable computing and SINET3 network support. We acknowledge support from MEXT, JSPS, and Nagoya's TLPRC (Japan); ARC and DIISR (Australia); NSFC (China); MSMT (Czechia); DST (India); MEST, NRF, NSDC of KISTI, and WCU (Korea); MNiSW (Poland); MES and RFAAE (Russia); ARRS (Slovenia); SNSF (Switzerland); NSC and MOE (Taiwan); and DOE (U.S.).