Eur. Phys. J. C 25, 421-425 (2002)
DOI: 10.1007/s10052-002-0974-2
Two photon width of
N. Fabiano1 and G. Pancheri2
1 Perugia University and INFN, via Pascoli 06100, Perugia, Italy
2 INFN National Laboratories, P.O. Box 13, 00044, Frascati, Italy
(Received: 25 October 2001 / Revised version: 7 March 2002 Published online: 30 August 2002 )
Abstract
We discuss the measured partial width of the pseudoscalar
charmonium state
into two photons.
Predictions from potential models are examined and compared with
experimental values. On including radiative corrections, it is found
that present measurements are compatible both with a
QCD type potential and with a static Coulomb potential.
The latter is then used to give
an estimate on the
decay into two photons.
Results for
are also compared with those
from
data through the NRQCD model.
© Società Italiana di Fisica, Springer-Verlag 2002
