We study hadronic transitions between bottomonium states using 496 fb-1 data collected at the ?(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e-collider. We measure B(?(4S)→π+π(1S))=(8.2±0.5(stat)±0.4(syst))×10-5, B(?(4S)→π+π(2S))=(7.9±1.0(stat)±0.4(syst))×10-5, and B(?(4S)→η?(1S))=(1.70±0.23(stat)±0.08(syst))×10-4. We measure the ratio of branching fractions R=B(?(4S)→η?(1S))/B(?(4S)→π+π(1S))=2.07±0.30(stat)±0.11(syst). We search for the decay ?(1D31,2)→η?(1S), but do not find significant evidence for such a transition. We also measure the initial-state radiation production cross sections of the ?(2S,3S) resonances and we find values compatible with the expected ones. Finally, the analysis of the ?(4S)→π+π(1S) events shows indications for a resonant contribution due to the f0(980) meson.
Bibliographical noteFunding Information:
We thank the KEKB group for the excellent operation of the accelerator; the KEK cryogenics group for the efficient operation of the solenoid; and the KEK computer group, the National Institute of Informatics, and the PNNL/EMSL computing group for valuable computing and SINET5 network support. We acknowledge support from the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan, the Japan Society for the Promotion of Science (JSPS), and the Tau-Lepton Physics Research Center of Nagoya University; the Australian Research Council; Austrian Science Fund under Grant No. P 26794-N20; the National Natural Science Foundation of China under Contracts No. 10575109, No. 10775142, No. 10875115, No. 11175187, No. 11475187, No. 11521505 and No. 11575017; the Chinese Academy of Science Center for Excellence in Particle Physics; the Ministry of Education, Youth and Sports of the Czech Republic under Contract No. LTT17020; the Carl Zeiss Foundation, the Deutsche Forschungsgemeinschaft, the Excellence Cluster Universe, and the VolkswagenStiftung; the Department of Science and Technology of India; the Istituto Nazionale di Fisica Nucleare of Italy; the WCU program of the Ministry of Education, National Research Foundation (NRF) of Korea Grants No. 2011-0029457, No. 2012-0008143, No. 2014R1A2A2A01005286, No. 2014R1A2A2A01002734, No. 2015R1A2A2A01003280, No. 2015H1A2A1033649, No. 2016R1D1A1B01010135, No. 2016K1A3A7A09005603, No. 2016K1A3A7A09005604, No. 2016R1D1A1B02012900, No. 2016K1A3A7A09005606, No. NRF-2013K1A3A7A06056592; the Brain Korea 21-Plus program, Radiation Science Research Institute, Foreign Large-size Research Facility Application Supporting project and the Global Science Experimental Data Hub Center of the Korea Institute of Science and Technology Information; the Polish Ministry of Science and Higher Education and the National Science Center; the Ministry of Education and Science of the Russian Federation and the Russian Foundation for Basic Research; the Slovenian Research Agency; Ikerbasque, Basque Foundation for Science and MINECO (Juan de la Cierva), Spain; the Swiss National Science Foundation; the Ministry of Education and the Ministry of Science and Technology of Taiwan; and the U.S. Department of Energy and the National Science Foundation.
© 2017 American Physical Society.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)