Observation of Υ(2S) → γη$_{b}$ (1S) Decay
Belle Collaboration; Fulsom, B. G.; Pedlar, T. K.; Adachi, I.; Aihara, H.; Al Said, S.; Asner, D. M.; Atmacan, H.; Aulchenko, V.; Aushev, T.; Ayad, R.; Babu, V.; Badhrees, I.; Bakich, A. M.; Bansal, V.; Behera, P.; Beleño, C.; Berger, M.; Bhardwaj, V.;
Abstract:
We report the observation of Υ(2S)→γηb(1S) decay based on an analysis of the inclusive photon spectrum of 24.7 fb−1 of e+e− collisions at the Υ(2S) center-of-mass energy collected with the Belle detector at the KEKB asymmetric-energy e+e− collider. We measure a branching fraction of B[Υ(2S)→γηb(1S)]=(6.1+0.6+0.9−0.7−0.6)×10−4 and derive an ηb(1S) mass of 9394.8+2.7+4.5−3.1−2.7 MeV/c2, where the uncertainties are statistical and systematic, respectively. The significance of our measurement is greater than 7 standard deviations, constituting the first observation of this decay mode.
| Zugehörige Institution(en) am KIT | Institut für Experimentelle Teilchenphysik (ETP) |
| Publikationstyp | Zeitschriftenaufsatz |
| Publikationsjahr | 2018 |
| Sprache | Englisch |
| Identifikator | ISSN: 0031-9007, 1079-7114 urn:nbn:de:swb:90-891587 KITopen-ID: 1000089158 |
| Erschienen in | Physical review letters |
| Verlag | American Physical Society (APS) |
| Band | 121 |
| Heft | 23 |
| Seiten | Article: 232001 |
| Bemerkung zur Veröffentlichung | Gefördert durch SCOAP3 |
| Vorab online veröffentlicht am | 03.12.2018 |
| Nachgewiesen in | Scopus Dimensions Web of Science |