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Title: Search for anomalous single top quark production in association with a photon in pp collisions at √(s) = 8 TeV

Journal Article · · Journal of High Energy Physics (Online)
 [1]
  1. Yerevan Physics Inst. (YerPhI) (Armenia). et al.

We found the results of a search for flavor changing neutral currents (FCNC) through single top quark production in association with a photon is presented. The study is based on proton-proton collisions at a center-of-mass energy of 8 TeV using data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 19.8 fb-1. The search for tγ events where t → Wb andW → μn is conducted in final states with a muon, a photon, at least one hadronic jet with at most one being consistent with originating from a bottom quark, and missing transverse momentum. Furthermore, there was no evidence of single top quark production in association with a photon through a FCNC is observed. Upper limits at the 95% confidence level are set on the tug and tcg anomalous couplings and translated into upper limits on the branching fraction of the FCNC top quark decays: B(t → uγ) < 1.3 x 10-4 and B(t →cγ) < 1.7 x 10-3. Upper limits are also set on the cross section of associated tγ production in a restricted phase-space region. These are the most stringent limits currently available.

Research Organization:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Organization:
CMS Collaboration
Grant/Contract Number:
AC02-07CH11359
OSTI ID:
1230041
Alternate ID(s):
OSTI ID: 22605233
Report Number(s):
FERMILAB-PUB--15-513-CMS; arXiv eprint number arXiv:1511.03951
Journal Information:
Journal of High Energy Physics (Online), Journal Name: Journal of High Energy Physics (Online) Journal Issue: 35 Vol. 2016; ISSN 1029-8479
Publisher:
Springer BerlinCopyright Statement
Country of Publication:
United States
Language:
English

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