EXCLUSIVE HEAVY-MESON PAIR PRODUCTION AT LARGE RECOIL

The Brodsky-Lepage (BL) formalism in perturbative QCD is applied to es timate the validity of the heavy-quark effective theory and the high-e nergy scaling laws to the exclusive heavy-meson pair production in two -photon collisions as well as e+e- annihilation. In addition to the or dinary heavy mesons such as B and D, the heavy mesons of which both qu ark masses are larger than the typical strong interaction scale LAMBDA (QCD) are considered. Explicit forms of transition amplitudes are pres ented for the heavy mesons with two heavy quarks in the peaking approx imation and the modifications for the ordinary heavy-meson production are described. The result in the heavy-quark a certain range of center of mass certain range of center of mass energy. In the high energy li mit, the transition amplitudes turn out to comply with the high energy scaling laws. The common features and different points of the e+e- an d gammagamma cases are described in detail. The limitation of the BL f ormalism and the heavy-quark effective theory is discussed.