We present an observation of photon-photon production of τ lepton pairs in ultraperipheral lead-lead collisions. The measurement is based on a data sample with an integrated luminosity of 404  μb^{-1} collected by the CMS experiment at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV. The γγ→τ^{+}τ^{-} process is observed for τ^{+}τ^{-} events with a muon and three charged hadrons in the final state. The measured fiducial cross section is σ(γγ→τ^{+}τ^{-})=4.8±0.6(stat)±0.5(syst)  μb, where the second (third) term corresponds to the statistical (systematic) uncertainty in σ(γγ→τ^{+}τ^{-}) in agreement with leading-order QED predictions. Using σ(γγ→τ^{+}τ^{-}), we estimate a model-dependent value of the anomalous magnetic moment of the τ lepton of a_{τ}=0.001_{-0.089}^{+0.055}.

Tumasyan, A., Adam, W., Andrejkovic, J., Bergauer, T., Chatterjee, S., Damanakis, K., et al. (2023). Observation of τ Lepton Pair Production in Ultraperipheral Pb-Pb Collisions at sqrt[s_{NN}]=5.02  TeV. PHYSICAL REVIEW LETTERS, 131(15), 151803 [10.1103/PhysRevLett.131.151803].

Observation of τ Lepton Pair Production in Ultraperipheral Pb-Pb Collisions at sqrt[s_{NN}]=5.02  TeV

Benaglia A.;Boldrini G.;Brivio F.;Cetorelli F.;De Guio F.;Dinardo M. E.;Ghezzi A.;Govoni P.;Guzzi L.;Lucchini M. T.;Malberti M.;Massironi A.;Moroni L.;Paganoni M.;Pinolini B. S.;Ragazzi S.;Tabarelli de Fatis T.;Zuolo D.;Gerosa R.;
2023

Abstract

We present an observation of photon-photon production of τ lepton pairs in ultraperipheral lead-lead collisions. The measurement is based on a data sample with an integrated luminosity of 404  μb^{-1} collected by the CMS experiment at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV. The γγ→τ^{+}τ^{-} process is observed for τ^{+}τ^{-} events with a muon and three charged hadrons in the final state. The measured fiducial cross section is σ(γγ→τ^{+}τ^{-})=4.8±0.6(stat)±0.5(syst)  μb, where the second (third) term corresponds to the statistical (systematic) uncertainty in σ(γγ→τ^{+}τ^{-}) in agreement with leading-order QED predictions. Using σ(γγ→τ^{+}τ^{-}), we estimate a model-dependent value of the anomalous magnetic moment of the τ lepton of a_{τ}=0.001_{-0.089}^{+0.055}.
Articolo in rivista - Articolo scientifico
LHC,CMS,ultraperipheral lead-lead collisions
English
2023
131
15
151803
none
Tumasyan, A., Adam, W., Andrejkovic, J., Bergauer, T., Chatterjee, S., Damanakis, K., et al. (2023). Observation of τ Lepton Pair Production in Ultraperipheral Pb-Pb Collisions at sqrt[s_{NN}]=5.02  TeV. PHYSICAL REVIEW LETTERS, 131(15), 151803 [10.1103/PhysRevLett.131.151803].
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/453725
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