Two-loop QCD correction to differential semi-leptonic b --> u decays in   the shape-function region
  We calculate the two-loop QCD correction to the form factors of on-shell b-quark decay to an energetic massless quark, which constitutes the last missing piece required for an O(alpha_s^2) determination of |V_ub| from inclusive semi-leptonic \bar B --> X_u l nu decays in the shape-function region. 
M. Beneke (RWTH Aachen University, University of Zurich), T. Huber   (RWTH Aachen University), Xin-Qiang Li (RWTH Aachen Uni...