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Title: Measurement of top quark polarisation in t-channel single top quark production

Abstract

Our first measurement of the top quark spin asymmetry, sensitive to the top quark polarisation, in t-channel single top quark production is presented. It is based on a sample of pp collisions at a centre-of-mass energy of 8 TeV corresponding to an integrated luminosity of 19.7 fb-1. A high-purity sample of t-channel single top quark events with an isolated muon is selected. Signal and background components are estimated using a fit to data. Furthermore, a differential cross section measurement, corrected for detector effects, of an angular observable sensitive to the top quark polarisation is performed. The differential distribution is used to extract a top quark spin asymmetry of 0.26 ± 0.03 (stat) ± 0.10 (syst), which is compatible with a p-value of 4.6% with the standard model prediction of 0.44.

Authors:
 [1]
  1. Yerevan Physics Inst. (YerPhI) (Armenia). et al.
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Org.:
CMS Collaboration
OSTI Identifier:
1230033
Report Number(s):
FERMILAB-PUB-15-518-CMS
Journal ID: ISSN 1029-8479; arXiv eprint number arXiv:1511.02138
Grant/Contract Number:  
AC02-07CH11359
Resource Type:
Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2016; Journal Issue: 73; Journal ID: ISSN 1029-8479
Publisher:
Springer Berlin
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Khachatryan, Vardan. Measurement of top quark polarisation in t-channel single top quark production. United States: N. p., 2016. Web. doi:10.1007/JHEP04(2016)073.
Khachatryan, Vardan. Measurement of top quark polarisation in t-channel single top quark production. United States. doi:10.1007/JHEP04(2016)073.
Khachatryan, Vardan. Wed . "Measurement of top quark polarisation in t-channel single top quark production". United States. doi:10.1007/JHEP04(2016)073. https://www.osti.gov/servlets/purl/1230033.
@article{osti_1230033,
title = {Measurement of top quark polarisation in t-channel single top quark production},
author = {Khachatryan, Vardan},
abstractNote = {Our first measurement of the top quark spin asymmetry, sensitive to the top quark polarisation, in t-channel single top quark production is presented. It is based on a sample of pp collisions at a centre-of-mass energy of 8 TeV corresponding to an integrated luminosity of 19.7 fb-1. A high-purity sample of t-channel single top quark events with an isolated muon is selected. Signal and background components are estimated using a fit to data. Furthermore, a differential cross section measurement, corrected for detector effects, of an angular observable sensitive to the top quark polarisation is performed. The differential distribution is used to extract a top quark spin asymmetry of 0.26 ± 0.03 (stat) ± 0.10 (syst), which is compatible with a p-value of 4.6% with the standard model prediction of 0.44.},
doi = {10.1007/JHEP04(2016)073},
journal = {Journal of High Energy Physics (Online)},
number = 73,
volume = 2016,
place = {United States},
year = {2016},
month = {4}
}

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