Study of Tau-pair Production in Photon-Photon Collisions at LEP and   Limits on the Anomalous Electromagnetic Moments of the Tau Lepton
  Tau-pair production in the process e+e- -> e+e-tau+tau- was studied using data collected by the DELPHI experiment at LEP2 during the years 1997 - 2000. The corresponding integrated luminosity is 650 pb^{-1}. The values of the cross-section obtained are found to be in agreement with QED predictions. Limits on the anomalous magnetic and electric dipole moments of the tau lepton are deduced. 
The DELPHI Collaboration, J. Abdallah, et al