A study of chi(b) meson production at LHCb is performed on proton-proton collision data, corresponding to 3.0 fb(-1) of integrated luminosity collected at centre-of-mass energies root s = 7 and 8 TeV. The fraction of gamma(nS) mesons originating from chi(b) decays is measured as a function of the gamma transverse momentum in the rapidity range 2.0 < y(gamma) < 4.5. The radiative transition of the chi(b) (3P) meson to gamma(3S) is observed for the first time. The chi(b)1 (3P) mass is determined to be m chi(b1) (3P) = 10 511.3 +/- 1.7 +/- 2.5MeV/c(2), where the first uncertainty is statistical and the second is systematic.
Jian Wang, Matthias Finger, Qian Wang, Yiming Li, João Miguel das Neves Duarte, Matthias Wolf, Varun Sharma, Yi Zhang, Tian Cheng, Yixing Chen, Alexis Kalogeropoulos, Ioannis Papadopoulos, Hua Zhang, Siyuan Wang, Xin Chen, Michele Bianco, Sebastiana Gianì, Sun Hee Kim, Rakesh Chawla, Jan Steggemann, Konstantin Androsov, Junqiu Liu, Anna Mascellani, Federica Legger, Matteo Galli, Gabriele Grosso
Jian Wang, Matthias Finger, Qian Wang, Yiming Li, João Miguel das Neves Duarte, Matthias Wolf, Varun Sharma, Yi Zhang, Tian Cheng, Yixing Chen, Alexis Kalogeropoulos, Ioannis Papadopoulos, Hua Zhang, Siyuan Wang, Xin Chen, Michele Bianco, Sebastiana Gianì, Sun Hee Kim, Davide Di Croce, Jian Zhao, Rakesh Chawla, Jan Steggemann, Konstantin Androsov, Anna Mascellani, Federica Legger, Matteo Galli, Gabriele Grosso