Publication at Faculty of Mathematics and Physics |
2013
Abstract
We report measurements of B -> chi(c1)gamma K and chi(c2)gamma K decays using 772 x 10(6) B((B) over bar) events collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. Evidence of a new resonance in the chi(c1)gamma final state is found with a statistical significance of 3.8 sigma.
This state has a mass of 3823.1 +/- 1.8(stat) +/- 0.7(syst) Mev/c(2), a value that is consistent with theoretical expectations for the previously unseen 1(3)D(2) c((c) over bar) meson. We find no other narrow resonance and set upper limits on the branching fractions of the X(3872) -> chi(c1)gamma and chi(c2)gamma decays.