Measurement of top quark polarisation in t-channel single top quark production
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.
- Publication Date:
- Report Number(s):
- FERMILAB-PUB-15-518-CMS
Journal ID: ISSN 1029-8479; arXiv eprint number arXiv:1511.02138
- Grant/Contract Number:
- AC02-07CH11359
- 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
- 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 Orgs:
- CMS Collaboration
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
- OSTI Identifier:
- 1230033