Search for top-quark decays t -> Hq with 36 fb(-1) of pp collision data at root s=13 TeV with the ATLAS detector
- NázevTitle
- Search for top-quark decays t -> Hq with 36 fb(-1) of pp collision data at root s=13 TeV with the ATLAS detectorSearch for top-quark decays t -> Hq with 36 fb(-1) of pp collision data at root s=13 TeV with the ATLAS detector
- Druh výsledkuResult type
- Článek v časopiseJournal article
- AutořiAuthors
- M. Aaboud, G. Aad, B. Abbott, O. Abdinov, B. Ali, K. Augsten, D. Caforio, P. Gallus, M. Havránek, Z. Hubáček, M. Myška, R. Novotný, S. Pospíšil, T. Slavíček, K. Smolek, M. Solar, A. Sopczak, M. Suk, V. Vacek, P. Vokáč, V. Vrba
- DOIDOI
- 10.1007/JHEP05(2019)123
- Časopis / citaceJournal / citation
- Journal of High Energy Physics. 2019, 2019(5), ISSN 1029-8479.
- RokYear
- 2019
- JazykLanguage
- eng
- WoSWoS
- 000468948900001
- ScopusScopus
- 2-s2.0-85066135451
- RIVRIV
- RIV/68407700:21220/19:00338143!RIV20-MSM-21220___
- ProjektProject
- Centrum pokročilých aplikovaných přírodních vědCenter for advanced applied sciences; Získávání nových poznatků o mikrosvětě v infrastruktuře CERNAcquiring new pieces of knowledge about micro-world in CERN research infrastructure
AbstraktAbstract
A search for flavour-changing neutral current decays of a top quark into an up-type quark (q = u, c) and the Standard Model Higgs boson, t Hq, is presented. The search is based on a dataset of pp collisions at = 13 TeV recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider and corresponding to an integrated luminosity of 36.1 fb(-1). Two complementary analyses are performed to search for top-quark pair events in which one top quark decays into Wb and the other top quark decays into Hq, and target the Hbb and H (+-) decay modes, respectively. The high multiplicity of b-quark jets, or the presence of hadronically decaying -leptons, is exploited in the two analyses respectively. Multivariate techniques are used to separate the signal from the background, which is dominated by top-quark pair production. No significant excess of events above the background expectation is found, and 95% CL upper limits on the t Hq branching ratios are derived. The combination of these searches with ATLAS searches in diphoton and multilepton final states yields observed (expected) 95% CL upper limits on the t Hc and t Hu branching ratios of 1.1 x 10(-3) (8.3 x 10(-4)) and 1.2 x 10(-3) (8.3 x 10(-4)), respectively. The corresponding combined observed (expected) upper limits on the |(tcH)| and |(tuH)| couplings are 0.064 (0.055) and 0.066 (0.055), respectively.
A search for flavour-changing neutral current decays of a top quark into an up-type quark (q = u, c) and the Standard Model Higgs boson, t Hq, is presented. The search is based on a dataset of pp collisions at = 13 TeV recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider and corresponding to an integrated luminosity of 36.1 fb(-1). Two complementary analyses are performed to search for top-quark pair events in which one top quark decays into Wb and the other top quark decays into Hq, and target the Hbb and H (+-) decay modes, respectively. The high multiplicity of b-quark jets, or the presence of hadronically decaying -leptons, is exploited in the two analyses respectively. Multivariate techniques are used to separate the signal from the background, which is dominated by top-quark pair production. No significant excess of events above the background expectation is found, and 95% CL upper limits on the t Hq branching ratios are derived. The combination of these searches with ATLAS searches in diphoton and multilepton final states yields observed (expected) 95% CL upper limits on the t Hc and t Hu branching ratios of 1.1 x 10(-3) (8.3 x 10(-4)) and 1.2 x 10(-3) (8.3 x 10(-4)), respectively. The corresponding combined observed (expected) upper limits on the |(tcH)| and |(tuH)| couplings are 0.064 (0.055) and 0.066 (0.055), respectively.