학술논문
Search for flavour-changing neutral tqH interactions with H → γγ in pp collisions at s = 13 TeV using the ATLAS detector
Document Type
Original Paper
Author
Source
Journal of High Energy Physics. 2023(12)
Subject
Language
English
ISSN
1029-8479
Abstract
Abstract: A search for flavour-changing neutral interactions involving the top quark, the Higgs boson and an up-type quark q (q = c, u) is presented. The proton-proton collision data set used, with an integrated luminosity of 139 fb−1 , was collected at stt¯bb¯ = 13 TeV by the ATLAS experiment at the Large Hadron Collider. Both the decay process t → qH in stt¯bb¯ production and the production process pp → tH, with the Higgs boson decaying into two photons, are investigated. No significant excess is observed and upper limits are set on the t → cH and the t → uH branching ratios of 4.3 × 10−4 and 3.8 × 10−4 , respectively, at the 95% confidence level, while the expected limits in the absence of signal are 4.7 × 10−4 and 3.9 × 10−4 . Combining this search with ATLAS searches in the H → τ+ τ− and H → stt¯bb¯ final states yields observed (expected) upper limits on the t → cH branching ratio of 5.8 × 10−4 (3.0 × 10−4 ) at the 95% confidence level. The corresponding observed (expected) upper limit on the t → uH branching ratio is 4.0 × 10−4 (2.4 × 10−4 ).