Pionic coupling constants of heavy mesons in the quark model

We analyse pionic couplings of heavy mesons combining PCAC with the dispers ion quark model to calculate the relevant transition form factors. Ground s tates and radial excitations are considered. For the ground state coupling constants the values (g) over cap = 0.5 +/- 0.02 in the heavy quark limit, and g(B*B pi) = 40 +/- 3, g(D*D pi) = 16 +/- 2 are obtained. A sizable supp ression of the coupling constants describing the pionic decays of the radia l excitations is observed. (C) 1999 Elsevier Science B.V. All rights reserv ed.