We develop a perturbative QCD factorization theorem for the semileptonic heavy baryon decay Λb →Λclν̄, whose form factors are expressed as the convolutions of hard b quark decay amplitudes with universal Λb and Λc baryon wave functions. Large logarithmic corrections are organized to all orders by Sudakov resummation, which renders perturbative expansions more reliable. It is observed that perturbative QCD is applicable to Λb→Λc decays for velocity transfer greater than 1.2. Under the requirement of heavy quark symmetry, we predict the branching ratio B(Λb→Λclν̄)∼2%, and determine the Λb and Λc baryon wave functions.
|Number of pages||9|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|State||Published - 1 Jun 2000|