Measurement of gamma gamma -> p p-bar production at Belle
arXiv:hep-ex/0503006 · doi:10.1016/j.physletb.2005.06.036
Abstract
A high precision study of the process gamma gamma -> p p-bar has been performed using a data sample of 89/fb collected with the Belle detector at the KEKB e+e- collider. The cross section of p p-bar production has been measured at two-photon center-of-mass (c.m.) energies between 2.025 and 4.0 GeV and in the c.m. angular range of |cos(theta^*)|<0.6. Production of gamma gamma -> eta_c -> p p-bar is observed and the product of the two-photon width of the eta_c and its branching ratio to p p-bar is determined.
20 pages, 9 figures, Fig.1 added, accepted for publication in Phys. Lett. B