Electroweak corrections to ${\tau }^{+}{\tau }^{-}$ production in ultraperipheral heavy-ion collisions at the LHC

Abstract

While the anomalous magnetic moments of the electron and the muon have been measured with remarkable precision, the magnetic moment of the $\tau$-lepton is only known to rather limited precision. A promising approach to measure it exploits ${\tau }^{+}{\tau }^{-}$ production in ultraperipheral collisions of lead ions at the LHC. In this article, a state-of-the-art theory prediction for ${\tau }^{+}{\tau }^{-}$ production including leptonic $\tau$-decays is provided. The impact of spin correlations between the $\tau$-leptons, of the masses of final-state leptons, of next-to-leading-order electroweak corrections, and of the parametrization of the photon flux are discussed.

Comments: 42 pages, latex, 11 figures. Text improved, numerics extended, version to appear in JHEP