Search for flavor-changing neutral currents in top quark decays t →hc and t →hu in multilepton final states in proton-proton collisions at s =13 TeV with the ATLAS detector

Summary, in English

Flavor-changing neutral currents are not present in the Standard Model at tree level and are suppressed in loop processes by the unitarity of the Cabibbo-Kobayashi-Maskawa matrix; the corresponding rates for top quark decay processes are experimentally unobservable. Extensions of the Standard Model can generate new flavor-changing neutral current processes, leading to signals which, if observed, would be unambiguous evidence of new interactions. A data set corresponding to an integrated luminosity of 36.1 fb-1 of pp collisions at a center-of-mass energy of s=13 TeV recorded with the ATLAS detector at the Large Hadron Collider is used to search for top quarks decaying to up or charm quarks with the emission of a Higgs boson, with subsequent Higgs boson decay to final states with at least one electron or muon. No signal is observed and limits on the branching fractions B(t→Hc)

• Author: M Aaboud; Torsten Åkesson; Simona Bocchetta; Eric Corrigan; Caterina Doglioni; Eva Brottmann Hansen; Vincent Hedberg; Göran Jarlskog; Charles Kalderon; Edgar Kellermann; Balazs Konya; Else Lytken; Katja Mankinen; Ulf Mjörnmark; Ruth Pöttgen; Trine Poulsen; Oxana Smirnova; Oleksandr Viazlo; L Zwalinski
• Department/s: Particle and nuclear physics; eSSENCE: The e-Science Collaboration
• Publishing year: 2018
• Language: English
• Publication/Series: Physical Review D
• Volume: 98
• Issue: 3
• Links: http://dx.doi.org/10.1103/PhysRevD.98.032002
• Document type: Journal article
• Publisher: American Physical Society
• Topic: Subatomic Physics
• Status: Published
• ISBN/ISSN/Other: ISSN: 2470-0010