General analysis of weak decay form factors in heavy to heavy and heavy to light baryon transitions

We present a complete analysis of the heavy to heavy and heavy to light baryon semi-leptonic decays in the heavy quark effective theory within the framework of a Bethe-Salpeter (BS) approach and demonstrate the equivalence of this approach to other work in the field. We present in a compact form the baryon BS amplitudes which incorporate the symmetries manifest in the heavy quark limit and which also show clearly the light quark dynamics. A similar form of the BS amplitude is presented for light baryons. Using the BS amplitudes, the heavy to heavy and heavy to light semi-leptonic baryon decays are considered. As expected there is a dramatic reduction in the number of form factors. An advant…