A sample of 114 +/- 11 B-s(0) -> J/psi K- pi(+) signal events obtained with 0.37 fb(-1) of pp collisions at root s = 7 TeV collected by the LHCb experiment is used to measure the branching fraction and polarization amplitudes of the B-s(0) -> J/psi(K) over bar*(0) decay, with (K) over bar*(0) -> K- pi(+). The K- pi(+) mass spectrum of the candidates in the B-s(0) peak is dominated by the (K) over bar*(0) contribution. Subtracting the nonresonant K- pi(+) component, the branching fraction of B-s(0) -> J/pi (K) over bar*(0) is (4.4(-0.4)(+0.5) +/- 0.8) x 10(-5), where the first uncertainty is statistical and the second is systematic. A fit to the angular distribution of the decay products yields the K*(0) polarization fractions f(L) = 0.50 +/- 0.08 +/- 0.02 and f(parallel to) = 0.19(-0.08)(+0.10) +/- 0.02.
Matthias Finger, Qian Wang, Yiming Li, Varun Sharma, Konstantin Androsov, Jan Steggemann, Xin Chen, Rakesh Chawla, Matteo Galli, Jian Wang, João Miguel das Neves Duarte, Tagir Aushev, Matthias Wolf, Yi Zhang, Tian Cheng, Yixing Chen, Werner Lustermann, Andromachi Tsirou, Alexis Kalogeropoulos, Andrea Rizzi, Ioannis Papadopoulos, Paolo Ronchese, Hua Zhang, Siyuan Wang, Tao Huang, David Vannerom, Michele Bianco, Sebastiana Gianì, Sun Hee Kim, Kun Shi, Abhisek Datta, Federica Legger, Gabriele Grosso, Anna Mascellani, Ji Hyun Kim, Donghyun Kim, Zheng Wang, Sanjeev Kumar, Wei Li, Yong Yang, Ajay Kumar, Ashish Sharma, Georgios Anagnostou, Joao Varela, Csaba Hajdu, Muhammad Ahmad, Ioannis Evangelou, Milos Dordevic, Meng Xiao, Sourav Sen, Xiao Wang, Kai Yi, Jing Li, Rajat Gupta, Hui Wang, Seungkyu Ha, Pratyush Das, Anton Petrov, Xin Sun, Valérie Scheurer, Muhammad Ansar Iqbal, Lukas Layer
Andreas Osterwalder, Viet Le Duc, Junwen Zou