Heavy meson masses in chiral perturbation theory with heavy quark symmetry

The SU(3) and hyperfine mass splittings of mesons containing a single heavy quark are computed to one-loop order in chiral perturbation theory with heavy quark spin symmetry. Electromagnetic contributions of order αem are included. The observed values of the mass splittings are consistent with the one-loop chiral perturbation theory calculation. The d-u hyperfine splitting [(D*+-D+)-(D*0-D0)] is equal to (md-mu)/ms times the s-d hyperfine splitting [(D*+s-D+s)-(D*+-D+)] up to electromagnetic contributions. The small observed value of the s-d hyperfine splitting implies that the d-u hyperfine splitting receives a significant electromagnetic mass contribution. (orig.)