Studies of heavy hadron physics
In the diquark picture, we establish Bethe-Salpeter equations for ground states of heavy baryons containing one heavy quark and two heavy quarks in the heavy quark limit, respectively. The Bethe-Salpeter equations for both heavy and light diquarks are also established. Assuming kernels to consist of a scalar confinement term and a one-gluon-exchange term we solve Bethe-Salpeter wave functions numerically in the covariant instantaneous approximation and give some applications including semileptonic and nonleptonic decay widths of heavy baryons, the average kinetic energy of the heavy quark in {Lambda}{sub Q}, {Sigma}{sub Q}{sup (*)}{yields}{Lambda}{sub Q}+{pi} decay widths, and heavy quark distribution functions. We also study possible molecular heavy bound states in the Bethe-Salpeter approach. Proof of QCD factorization for {Lambda}{sub b}{yields}{Lambda}{sub c}{pi} is presented in the framework of QCD factorization.