Measurement of the gamma gamma* --> eta_c transition form factor
High Energy Physics - Experiment
2010-05-27 v2
Abstract
We study the reaction e+e- --> e+e- eta_c, eta_c --> K_S K+- pi-+ and obtain eta_c mass and width values 2982.2+-0.4+-1.6 MeV/c^2 and 31.7+-1.2+-0.8 MeV, respectively. We find Gamma(eta_c --> gamma gamma)B(eta_c --> K anti-K pi)=0.374+-0.009+-0.031 keV, and measure the gamma gamma* --> eta_c transition form factor in the momentum transfer range from 2 to 50 GeV^2. The analysis is based on 469 fb-1 of integrated luminosity collected at PEP-II with the BABAR detector at e+e- center-of-mass energies near 10.6 GeV.
Keywords
Cite
@article{arxiv.1002.3000,
title = {Measurement of the gamma gamma* --> eta_c transition form factor},
author = {The BABAR Collaboration and J. P. Lees},
journal= {arXiv preprint arXiv:1002.3000},
year = {2010}
}
Comments
20 pages, 26 postscript figures, updated to version accepted for publication in Phys. Rev. D