Электронный каталог

Статья

Hayrapetyan, A.
Observation of *g*g*>*t*t in Proton-Proton Collisions and Limits on the Anomalous Electromagnetic Moments of the *t Lepton / A.Hayrapetyan, S.Afanasiev, D.Budkouski, I.Golutvin, I.Gorbunov, V.Karjavine, V.Korenkov, N.Krasnikov, A.Lanev, A.Malakhov, V.Matveev, V.Palichik, V.Perelygin, M.Savina, V.Shalaev, S.Shmatov, S.Shulha, V.Smirnov, O.Teryaev, N.Voytishin, B.S.Yuldashev, A.Zarubin, I.Zhizhin, Z.Tsamalaidze, [CMS Collab.] // Reports on Progress in Physics [Electronic resource]. – 2024. – Vol. 87, No. 10. – P. 107801. – URL: https://doi.org/10.1088/1361-6633/ad6fcb. – Bibliogr.: 76.

The production of a pair of τ leptons via photon–photon fusion, γγ → ττ, is observed for the first time in proton–proton collisions, with a significance of 5.3 standard deviations. This observation is based on a data set recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV and corresponding to an integrated luminosity of 138 fb−1. Events with a pair of τ leptons produced via photon–photon fusion are selected by requiring them to be back-to-back in the azimuthal direction and to have a minimum number of charged hadrons associated with their production vertex. The τ leptons are reconstructed in their leptonic and hadronic decay modes. The measured fiducial cross section of γγ → ττ is σ&sup(fid)&sub(obs)= 2.4&sup(+3.8)&sub(−3.1)fb. Constraints are set on the contributions to the anomalous magnetic moment (a&sub(τ)) and electric dipole moments (d&sub(τ)) of the τ lepton originating from potential effects of new physics on the γττ vertex: a&sub(τ) =.0009&sup(+0.0032)&sub(−0.0031) and |dτ| < 2.9 × 10−17 e cm (95% confidence level), consistent with the standard model.



ОИЯИ = ОИЯИ (JINR)2024
Спец.(статьи,препринты) = С 346.2в - Взаимодействие протонов с протонами
Спец.(статьи,препринты) = С 346.6е1 - Рождение прямых лептонов в соударениях элементарных частиц. Новые лептоны. Тау- лептон