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arXiv · 2307.07481

BSM physics using photon-photon fusion processes in UPC in Pb+Pb collisions with the ATLAS detector

Klaudia Maj
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Abstract

Relativistic heavy-ion beams at the LHC are accompanied by a large flux of equivalent photons, leading to multiple photon-induced processes. This proceeding presents searches for physics beyond the Standard Model enabled by photon-photon processes in both di-tau and diphoton final states. The tau-pair production measurements can constrain the tau lepton's anomalous magnetic dipole moment (g-2), and a recent ATLAS measurement using muonic decays of tau leptons in association with electrons and tracks provides one of the most stringent limits available to date. Similarly, light-by-light scattering proceeds via loop diagrams, which can contain particles not yet directly observed. Thus, high statistics measurements of light-by-light scattering provide a precise and unique opportunity to investigate extensions of the Standard Model, such as the presence of axion-like particles.

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Klaudia Maj. 2023-07-14. BSM physics using photon-photon fusion processes in UPC in Pb+Pb collisions with the ATLAS detector. https://arxiv.org/abs/2307.07481

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