Factorization of heavy-to-light baryonic transitions in SCET

Wei Wang
2012 Physics Letters B  
In the framework of the soft-collinear effective theory, we demonstrate that the leading-power heavy-to-light baryonic form factors at large recoil obey the heavy quark and large energy symmetries. Symmetry breaking effects are suppressed by Λ/m_b or Λ/E, where Λ is the hadronic scale, m_b is the b quark mass and E∼ m_b is the energy of light baryon in the final state. At leading order, the leading power baryonic form factor ξ_Λ,p(E), in which two hard-collinear gluons are exchanged in the
more » ... changed in the baryon constituents, can factorize into the soft and collinear matrix elements convoluted with a hard-kernel of order α_s^2. Including the energy release dependence, we derive the scaling law ξ_Λ,p(E)∼Λ^2 /E^2. We also find that this form factor ξ_Λ(E) is numerically smaller than the form factor governed by soft processes, although the latter is formally power-suppressed.
doi:10.1016/j.physletb.2012.01.036 fatcat:xnsteia44van7cxvvkn6kfkxda