Matching Parton Shower and matrix elements in QED
  We report on a high-precision calculation of the Bhabha process in QED, of interest for precise luminosity determination of low-energy electron-positron colliders. The calculation is based on the matching of exact next-to-leading order corrections with a Parton Shower algorithm. The structure of the algorithm (implemented in an improved version of the event generator BABAYAGA) is illustrated, with a discussion on the resulting theoretical uncertainty, of the order of 0.1 %. 
G. Balossini, C.M. Carloni Calame, G. Montagna, O. Nicrosini, F.   Piccinini