Observation of the γγ→ττ Process in Pb+Pb Collisions and Constraints on the τ -Lepton Anomalous Magnetic Moment with the ATLAS Detector : = Observation of the [gamma][gamma][square root]s[tau][tau] process in Pb+Pb collisions and constraints on the [tau]-lepton anomalous magnetic moment with the ATLAS detector

Abstract: This Letter reports the observation of τ-lepton-pair production in ultraperipheral lead-lead collisions Pb+Pb→Pb(γγ→ττ)Pb and constraints on the τ-lepton anomalous magnetic moment aτ. The dataset corresponds to an integrated luminosity of 1.44  nb−1 of LHC Pb+Pb collisions at √sNN=5.02  TeV recorded by the ATLAS experiment in 2018. Selected events contain one muon from a τ-lepton decay, an electron or charged-particle track(s) from the other τ-lepton decay, little additional central-detector activity, and no forward neutrons. The γγ→ττ process is observed in Pb+Pb collisions with a significance exceeding 5 standard deviations and a signal strength of μττ=1.03+0.06−0.05 assuming the standard model value for aτ. To measure aτ, a template fit to the muon transverse-momentum distribution from τ-lepton candidates is performed, using a dimuon (γγ→μμ) control sample to constrain systematic uncertainties. The observed 95% confidence-level interval for aτ is −0.057

Object Details

• Alternative title: Observation of the [gamma][gamma][square root]s[tau][tau] process in Pb+Pb collisions and constraints on the [tau]-lepton anomalous magnetic moment with the ATLAS detector
• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: Physical review letters. - 131, 15 (2023) , 151802, ISSN: 1079-7114

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Universität
• (when): 2023
• Creator: Argyropoulos, Spyridon ; Becherer, Fabian ; Böhler, Michael ; Diehl, Leena ; Fernandez Pretel, Jose Antonio ; Froch, Alexander ; Gargiulo, Simona ; Gurdasani, Simran Sunil ; Heidegger, Constantin ; Heidegger, Kim K. ; Hermann, Leonie ; Herten, Gregor ; Hohn, David ; Hönig, Jan Cedric ; Jakobs, Karl ; Jenni, Peter ; Karentzos, Efstathios ; Knue, Andrea ; Köneke, Karsten ; Kuprash, Oleg ; Landgraf, Ulrich ; Lang, Valerie ; Lösle, Alena ; Magerl, Veronika ; Moskalets, Tetiana ; Öncel, Ömer Ogul ; Parzefall, Ulrich ; Plesanovs, Vladislavs ; Rafanoharana, Dimbiniaina ; Rodríguez Rodríguez, Arturo ; Roland, Benoit ; Rottler, Benjamin ; Rühr, Frederik ; Rúriková, Zuzana ; Sammel, Dirk ; Sauerburger, Frank ; Schleicher, Katharina E. ; Scholer, Patrick ; Schumacher, Markus ; Solomon, Shalu ; Solovieva, Ksenia ; Sperlich, Dennis ; Weiser, Christian ; Wiik-Fuchs, Liv ; Winter, Benedict T. ; Young, Christopher ; Zanzi, Daniele ; ATLAS Collaboration CERN, [Study Group] ; et al
• Contributor: Experimentelle Teilchenphysik, Abt. Prof. Dr. Gregor Herten ; Experimentelle Teilchenphysik, Abt. Prof. Karl Jakobs ; Experimentelle Teilchenphysik, Abt. Prof. Schumacher

Further information

• DOI: 10.1103/physrevlett.131.151802
• URN: urn:nbn:de:bsz:25-freidok-2423315
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 15.08.2025, 7:38 AM CEST