B to light meson transition form factors calculated in perturbative QCD approachC.-D. Lü and M.-Z. Yang
CCAST (World Laboratory), P.O. Box 8730, Beijing 100080, P.R. China and Institute of High Energy Physics, P.O. Box 918(4), Beijing 100039, P.R. China
(Received: 27 December 2002 / Published online: 5 May 2003)
We calculate the , ( P is the light pseudoscalar meson, V the light vector meson) form factors in the large-recoil limit in the perturbative QCD approach, including both the vector (axial vector) and tensor operators. In general there are two leading components and for the B meson wave functions. We consider both contributions of them. Sudakov effects ( and threshold resummation) are included to regulate the soft end-point singularity. By choosing the hard scale as the maximum virtualities of the internal particles in the hard b quark decay amplitudes, Sudakov factors can effectively suppress the long-distance soft contribution. The hard contribution can be dominant in these approaches.
© Società Italiana di Fisica, Springer-Verlag 2003