The electromagnetic masses of charmed pseudoscalar mesons

Heavy-quark effective theory (HQET) and Chiral perturbation theory at the quark level (ChPT)q, based on the extended Nambu-Jona-Lasinio model with linear realization of chiral U(3) × U(3) symmetry, are applied to the computation of electromagnetic masses of charmed pseudoscalar mesons. The result of the computation of the electromagnetic mass can be represented in the form of the low-energy theorem like Dashenʹs theorem. Chiral logarithm contributions to the mass difference MD+ − MD0 are computed.