1. Department of Physics, Nanjing University, Nanjing 210093,
China
;2. CCAST (World Laboratory), P.O. Box 8730, Beijing 100080, China
;3. Department of Physics, Nanjing Normal University,
Nanjing 210097, China
Abstract:
A method for obtaining the small current quark mass effect on the
dressed quark propagator within the Dyson-Schwinger approach is developed.
From this the small current quark mass dependence of the bag constant is
evaluated. It is found that the bag constant decreases with the increasing
current quark mass and the contribution of the current quark mass cannot
be dropped.