Evidence for B+ -> h(c)K(+) and observation of eta(c()2S) -> p(p)over-bar pi(+)pi(-)

A search for the decays B+ -> h(c)K(+) and B-0 -> h(c)K(S)(0) is performed. Evidence for the decay B+ -> h(c)K(+) is found; its significance is 4.8 sigma. No evidence is found for B-0 -> h(c)K(S)(0). The branching fraction for B+ -> h(c)K(+) is measured to be (3.7(-0.9 -0.8)(+1.0 +038)) x 10(-5); the upper limit for the B-0 -> h(c)K(S)(0) branching fraction is 1.4 x 10(-5) at 90% C. L. In addition, a study of the p (p) over bar pi(+pi-) invariant mass distribution in the channel B+ -> (p (p) over bar (+)pi(-))K+ results in the first observation of the decay eta(c)(2S) -> p (p) over bar pi(+)pi(-) with 12.1 sigma significance. The analysis is based on the 711 fb(-1) data sample collected by the Belle detector at the asymmetric- energy e(+)e(-) collider KEKB at the gamma(4S) resonance.We thank the KEKB group for the excellent operation of the accelerator; the KEK cryogenics group for the efficient operation of the solenoid; the KEK computer group and the Pacific Northwest National Laboratory (PNNL) Environmental Molecular Sciences Laboratory (EMSL) computing group for strong computing support; and the National Institute of Informatics, and Science Information NETwork 5 (SINET5) for valuable 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 including Grants No. DP180102629, No. DP170102389, No. DP170102204, No. DP150103061, and No. FT130100303; Austrian Science Fund (FWF); the National Natural Science Foundation of China under Contracts No. 11435013, No. 11475187, No. 11521505, No. 11575017, No. 11675166, and No. 11705209; Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS), Grant No. QYZDJ-SSW-SLH011; the CAS Center for Excellence in Particle Physics (CCEPP); the Shanghai Pujiang Program under Grant No. 18PJ1401000; 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; National Research Foundation (NRF) of Korea Grants No. 2015H1A2A1033649, No. 2016R1D1A1B01010135, No. 2016K1 A3A7A09005 603, No. 2016R1D1A1B02012900, No. 2018R1A2B3003 643, No. 2018R1A6A1A06024970, and No. 2018R1D1 A1B07047294; Radiation Science Research Institute, Foreign Large-size Research Facility Application Supporting project, the Global Science Experimental Data Hub Center of the Korea Institute of Science and Technology Information and Korea Research Environment Open Network/Global Ring Network for Advanced Application Development; the Polish Ministry of Science and Higher Education and the National Science Center; the Russian Foundation for Basic Research Grant No. 18-32-00277; the Slovenian Research Agency; Ikerbasque, Basque Foundation for Science, Spain; the Swiss National Science Foundation; the Ministry of Education and the Ministry of Science and Technology of Taiwan; and the United States Department of Energy and the National Science Foundation