τ-pair production via photon-photon collisions at the CERNe+e−collider LEP

We point out that the cross section for the process ${\mathit{e}}^{+}$ ${\mathit{e}}^{\mathrm{-}}$→${\mathit{e}}^{+}$ ${\mathit{e}}^{\mathrm{-}}$ ${\mathrm{\tau }}^{+}$ ${\mathrm{\tau }}^{\mathrm{-}}$ at CERN LEP is large enough to allow for a study of the anomalous electromagnetic couplings of the τ lepton. We show that competitive bounds for the magnetic and electric dipole moments can be obtained using the data taken from 1992 to 1994. Finally, we show how these bounds can be improved at LEP II. © 1996 The American Physical Society.