Электронный каталог

Статья

Hayrapetyan, A.
Measurement of the *t Lepton Polarization in Z Boson Decays in Proton-Proton Collisions at *%s=13 TeV / A.Hayrapetyan, S.Afanasiev, D.Budkouski, I.Golutvin, I.Gorbunov, V.Karjavine, V.Korenkov, 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, N.Krasnikov, [CMS Collab.] // Journal of High Energy Physics [Electronic resource]. – 2024. – Vol. 2024, No. 1. – P. 101. – URL: https://doi.org/10.1007/JHEP01(2024)101. – Bibliogr.: 46.

The polarization of τ leptons is measured using leptonic and hadronic τ lepton decays in Z → τ +τ − events in proton-proton collisions at √s = 13 TeV recorded by CMS at the CERN LHC with an integrated luminosity of 36.3 fb−1. The measured τ − lepton polarization at the Z boson mass pole is Pτ (Z) = −0.144 ± 0.006 (stat) ± 0.014 (syst) = −0.144 ± 0.015, in good agreement with the measurement of the τ lepton asymmetry parameter of Aτ = 0.1439 ± 0.0043 = −Pτ (Z) at LEP. The τ lepton polarization depends on the ratio of the vector to axial-vector couplings of the τ leptons in the neutral current expression, and thus on the effective weak mixing angle sin2 θeff W, independently of the Z boson production mechanism. The obtained value sin2 θeff W = 0.2319 ± 0.0008(stat) ± 0.0018(syst) = 0.2319 ± 0.0019 is in good agreement with measurements at e+e− colliders.



ОИЯИ = ОИЯИ (JINR)2024
Спец.(статьи,препринты) = С 346.2в - Взаимодействие протонов с протонами
Спец.(статьи,препринты) = С 346.6е2 - Промежуточные бозоны