Vub from the hadronic invariant mass spectrum in semileptonic B decay

The hadronic invariant mass spectrum for the inclusive charmless semileptonic decay B → Xueνe is studied. Particular attention is paid to the region sh < md2, which may be useful for extracting the value of |Vub|. The se of the spectrum to the parameter Λ ≡ mb − mb is explored. Perturbative QCD corrections to dΓ/dsh of order αs2β0 are calculated. For sh ∼ Λ mb nonperturbative QCD effects are important and the shape of the invariant mass spectrum is controlled by the B meson matrix element of an infinite sum of local operators. The utility of the hadronic mass spectrum for extracting |Vub| is explored.