A Parton Model for Inclusive Semileptonic B Meson Decays
  The parton model for semileptonic B meson decays is studied with special attention to the decay distributions. We find that the spectra show dramatic variations when we introduce cuts on the hadronic energy or invariant mass of hadrons. Results for both $b\rightarrow u$ and $b\rightarrow c$ decays are presented. The detailed spectra may help to separate the two types of decays. 
C.H.Jin, W.F.Palmer, E.A.Paschos