PT Journal
AU BABAR Collaboration (Lees, JPea
   Azzolini, V
   Lopez-March, N
   Martinez-Vidal, F
   Milanes, DA
   Oyanguren, A
TI Measurement of the gamma gamma* -> eta c transition form factor
SO Physical Review D
JI Phys. Rev. D
PY 2010
BP 052010
EP 18pp
VL 81
IS 5
DI 10.1103/PhysRevD.81.052010
LA English
AB We study the reaction e(+)e(-) -> e(+)e(-) eta(c), eta(c) -> KSK +/-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) -> KK 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 GeV2. 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.
ER