https://doi.org/10.1007/s100520200920
Dynamical relativistic corrections to the leptonic decay width of heavy quarkonia
Laboratoire de Physique Corpusculaire, Université Blaise-Pascal, CNRS/IN2P3, 24 avenue des Landais,
63177 Aubière Cedex, France
Corresponding authors: a bissey@in2p3.fr - b dugne@clermont.in2p3.fr - c mathiot@in2p3.fr
Received:
6
December
2001
Published online:
6
April
2002
We calculate the dynamical relativistic corrections, originating from radiative one-gluon exchange, to the leptonic decay width of heavy quarkonia in the framework of a covariant formulation of light-front dynamics. Comparison with the non-relativistic calculations of the leptonic decay width of J = 1 charmonium and bottomonium S-ground states shows that relativistic corrections are large. Most importantly, the calculation of these dynamical relativistic corrections legitimate a perturbative expansion in αs, even in the charmonium sector. This is in contrast with the ongoing belief based on calculations in the non-relativistic limit. Consequences for the ability of several phenomenological potentials to describe these decays are described.
© Società Italiana di Fisica, Springer-Verlag, 2002