Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at √𝑠 = 13 TeV
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...
| Main Authors: | , , , , , , , , , , , , , , , , , |
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| Other Authors: | |
| Format: | Article |
| Language: | English |
| Published: |
Springer Berlin Heidelberg
2024
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| Online Access: | https://hdl.handle.net/1721.1/153399 |
| _version_ | 1824458279317667840 |
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| author | Hayrapetyan, A. Tumasyan, A. Adam, W. Andrejkovic, J. W. Bergauer, T. Chatterjee, S. Damanakis, K. Dragicevic, M. Escalante Del Valle, A. Hussain, P. S. Jeitler, M. Krammer, N. Liko, D. Mikulec, I. Schieck, J. Schöfbeck, R. Schwarz, D. Sonawane, M. |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Hayrapetyan, A. Tumasyan, A. Adam, W. Andrejkovic, J. W. Bergauer, T. Chatterjee, S. Damanakis, K. Dragicevic, M. Escalante Del Valle, A. Hussain, P. S. Jeitler, M. Krammer, N. Liko, D. Mikulec, I. Schieck, J. Schöfbeck, R. Schwarz, D. Sonawane, M. |
| author_sort | Hayrapetyan, A. |
| collection | MIT |
| description | 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
$$ \sqrt{s} $$
= 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
P
τ
Z
$$ {\mathcal{P}}_{\tau}\left(\textrm{Z}\right) $$
= −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 =
−
P
τ
Z
$$ -{\mathcal{P}}_{\tau}\left(\textrm{Z}\right) $$
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
θ
W
eff
$$ {\theta}_{\textrm{W}}^{\textrm{eff}} $$
, independently of the Z boson production mechanism. The obtained value sin2
θ
W
eff
$$ {\theta}_{\textrm{W}}^{\textrm{eff}} $$
= 0.2319 ± 0.0008(stat) ± 0.0018(syst) = 0.2319 ± 0.0019 is in good agreement with measurements at e+e− colliders. |
| first_indexed | 2024-09-23T14:16:10Z |
| format | Article |
| id | mit-1721.1/153399 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2025-02-19T04:23:22Z |
| publishDate | 2024 |
| publisher | Springer Berlin Heidelberg |
| record_format | dspace |
| spelling | mit-1721.1/1533992025-01-03T04:37:43Z Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at √𝑠 = 13 TeV Hayrapetyan, A. Tumasyan, A. Adam, W. Andrejkovic, J. W. Bergauer, T. Chatterjee, S. Damanakis, K. Dragicevic, M. Escalante Del Valle, A. Hussain, P. S. Jeitler, M. Krammer, N. Liko, D. Mikulec, I. Schieck, J. Schöfbeck, R. Schwarz, D. Sonawane, M. Massachusetts Institute of Technology. Department of Physics 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 $$ \sqrt{s} $$ = 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 P τ Z $$ {\mathcal{P}}_{\tau}\left(\textrm{Z}\right) $$ = −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 = − P τ Z $$ -{\mathcal{P}}_{\tau}\left(\textrm{Z}\right) $$ 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 θ W eff $$ {\theta}_{\textrm{W}}^{\textrm{eff}} $$ , independently of the Z boson production mechanism. The obtained value sin2 θ W eff $$ {\theta}_{\textrm{W}}^{\textrm{eff}} $$ = 0.2319 ± 0.0008(stat) ± 0.0018(syst) = 0.2319 ± 0.0019 is in good agreement with measurements at e+e− colliders. 2024-01-23T20:14:56Z 2024-01-23T20:14:56Z 2024-01-19 2024-01-21T04:22:12Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/153399 Journal of High Energy Physics. 2024 Jan 19;2024(1):101 PUBLISHER_CC en https://doi.org/10.1007/JHEP01(2024)101 Creative Commons Attribution https://creativecommons.org/licenses/by/4.0/ The Author(s) application/pdf Springer Berlin Heidelberg Springer Berlin Heidelberg |
| spellingShingle | Hayrapetyan, A. Tumasyan, A. Adam, W. Andrejkovic, J. W. Bergauer, T. Chatterjee, S. Damanakis, K. Dragicevic, M. Escalante Del Valle, A. Hussain, P. S. Jeitler, M. Krammer, N. Liko, D. Mikulec, I. Schieck, J. Schöfbeck, R. Schwarz, D. Sonawane, M. Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at √𝑠 = 13 TeV |
| title | Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at √𝑠 = 13 TeV |
| title_full | Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at √𝑠 = 13 TeV |
| title_fullStr | Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at √𝑠 = 13 TeV |
| title_full_unstemmed | Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at √𝑠 = 13 TeV |
| title_short | Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at √𝑠 = 13 TeV |
| title_sort | measurement of the τ lepton polarization in z boson decays in proton proton collisions at √𝑠 13 tev |
| url | https://hdl.handle.net/1721.1/153399 |
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