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

doi:10.1007/JHEP04(2016)073

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:

Khachatryan, Vardan ^[1]

Yerevan Physics Inst. (YerPhI) (Armenia). et al.

Publication Date:: 2016-04-13

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.

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                    Khachatryan, Vardan. Measurement of top quark polarisation in t-channel single top quark production.  United States.  doi:10.1007/JHEP04(2016)073.

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                    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.

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@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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DOI: 10.1007/JHEP04(2016)073

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