Evidence for the Associated Production of a Single Top Quark and a Photon in Proton-Proton Collisions at √s=13  TeV

Bibliographische Detailangaben
Parent link:Physical Review Letters: Scientific Journal.— , 1958-
Vol. 121, iss. 22.— 2018.— [221802, 18 p.]
Körperschaften: Национальный исследовательский Томский политехнический университет Исследовательская школа физики высокоэнергетических процессов, Национальный исследовательский Томский политехнический университет Инженерная школа новых производственных технологий Научно-производственная лаборатория "Импульсно-пучковых, электроразрядных и плазменных технологий"
Weitere Verfasser: Sirunyan A. M., Tumasyan A. R., Adam W. Wolfgang, Ambrogi F. Federico, Babaev A. A. Anton Anatoljevich, Okhotnikov V. V. Vitaly Vladimirovich
Zusammenfassung:Title screen
The first evidence of events consistent with the production of a single top quark in association with a photon is reported. The analysis is based on proton-proton collisions at √s=13  TeV and recorded by the CMS experiment in 2016, corresponding to an integrated luminosity of 35.9  fb−1. Events are selected by requiring the presence of a muon (μ), a photon (γ), an imbalance in transverse momentum from an undetected neutrino (ν), and at least two jets (j) of which exactly one is identified as associated with the hadronization of a b quark. A multivariate discriminant based on topological and kinematic event properties is employed to separate signal from background processes. An excess above the background-only hypothesis is observed, with a significance of 4.4 standard deviations. A fiducial cross section is measured for isolated photons with transverse momentum greater than 25 GeV in the central region of the detector. The measured product of the cross section and branching fraction is σ(pp→tγj)B(t→μνb)=115±17(stat)±30(syst)  fb, which is consistent with the standard model prediction.
Режим доступа: по договору с организацией-держателем ресурса
Sprache:Englisch
Veröffentlicht: 2018
Schlagworte:
Online-Zugang:https://doi.org/10.1103/PhysRevLett.121.221802
Format: Elektronisch Buchkapitel
KOHA link:https://koha.lib.tpu.ru/cgi-bin/koha/opac-detail.pl?biblionumber=658883
Beschreibung
Zusammenfassung:Title screen
The first evidence of events consistent with the production of a single top quark in association with a photon is reported. The analysis is based on proton-proton collisions at √s=13  TeV and recorded by the CMS experiment in 2016, corresponding to an integrated luminosity of 35.9  fb−1. Events are selected by requiring the presence of a muon (μ), a photon (γ), an imbalance in transverse momentum from an undetected neutrino (ν), and at least two jets (j) of which exactly one is identified as associated with the hadronization of a b quark. A multivariate discriminant based on topological and kinematic event properties is employed to separate signal from background processes. An excess above the background-only hypothesis is observed, with a significance of 4.4 standard deviations. A fiducial cross section is measured for isolated photons with transverse momentum greater than 25 GeV in the central region of the detector. The measured product of the cross section and branching fraction is σ(pp→tγj)B(t→μνb)=115±17(stat)±30(syst)  fb, which is consistent with the standard model prediction.
Режим доступа: по договору с организацией-держателем ресурса
DOI:10.1103/PhysRevLett.121.221802