Luminosity monitors at the LHC
  We study the theoretical accuracy of various methods that have been proposed to measure the luminosity of the LHC pp collider, as well as for Run II of the Tevatron p barp collider. In particular we consider methods based on   (i) the total and forward elastic data, (ii) lepton-pair production and (iii) W and Z production. 
V.A. Khoze (Durham), A.D. Martin (Durham), R. Orava (Helsinki), M.G.   Ryskin (St. Petersburg)