Feasibility at the LHC, FCC-he and CLIC for Sensitivity Estimates on Anomalous Electromagnetic Couplings of the τ-lepton

Abstract

In this paper, we present detailed studies for measuring the production cross sections and setting model independent limits on the anomalous magnetic and electric dipole moments $\tilde {a}_{\tau }$ and $\tilde {d}_{\tau }$ of the τ-lepton, through the tau pair production channels $pp \to p\tau \bar \tau \gamma p$, $e^{-}p \to e^{-} \tau \bar \tau \gamma p$ and $e^{+}e^{-} \to e^{+} \tau \bar \tau \gamma e^{-}$ via the γ^∗γ^∗→ τ⁺τ⁻γ subprocess. Measurements of the anomalous electromagnetic couplings of the tau-lepton provide an excellent opportunity to probe extensions of the Standard Model. We found that of the three colliders considered LHC, FCC-he and CLIC, the prediction of the future CLIC at high energy and high luminosity should provide the best sensitivity on the dipole moments of the τ-lepton $\tilde a_{\tau }= [-0.00128, 0.00105]$ and $|\tilde {d}_{\tau }(\text {ecm})|= 6.4394\times 10^{-18}$ at the 95% Confidence Level. Our results also project better sensitivity than those reported by the DELPHI and BELLE collaborations.