Evidence of off-shell Higgs boson production from ZZ leptonic decay channels and constraints on its total width with the ATLAS detector

0579141 - FZÚ 2024 RIV NL eng J - Journal Article
Aad, G. - Abbott, B. - Abeling, K. - Chudoba, Jiří - Federičová, Pavla - Hejbal, Jiří - Jačka, Petr - Kepka, Oldřich - Kroll, Jiří - Kupčo, Alexander - Latoňová, Věra - Lokajíček, Miloš - Lysák, Roman - Marčišovský, Michal - Mikeštíková, Marcela - Němeček, Stanislav - Šícho, Petr - Staroba, Pavel - Svatoš, Michal - Taševský, Marek … Total 2835 authors
Evidence of off-shell Higgs boson production from ZZ leptonic decay channels and constraints on its total width with the ATLAS detector.
Physics Letters. B. Roč. 846, Nov (2023), č. článku 138223. ISSN 0370-2693. E-ISSN 1873-2445
Research Infrastructure: CERN-CZ III - 90240
Institutional support: RVO:68378271
Keywords : underlying event * Higgs particle: width * p p: scattering * Z0: pair production
OECD category: Particles and field physics
Impact factor: 4.3, year: 2022
Method of publishing: Open access

This Letter reports on a search for off-shell production of the Higgs boson using 139 fb−1 of pp collision data at s= 13 TeV collected by the ATLAS detector at the Large Hadron Collider. The signature is a pair of Z bosons, with contributions from both the production and subsequent decay of a virtual Higgs boson and the interference of that process with other processes. The two observable final states are ZZ→4ℓ and ZZ→2ℓ2ν with ℓ=e or μ. In the ZZ→4ℓ final state, a dense Neural Network is used to enhance analysis sensitivity with respect to matrix element-based discrimination. The background-only hypothesis is rejected with an observed (expected) significance of 3.3 (2.2) standard deviations, representing experimental evidence for off-shell Higgs boson production. Assuming that no new particles enter the production of the virtual Higgs boson, its total width can be deduced from the measurement of its off-shell production cross-section.

Permanent Link: https://hdl.handle.net/11104/0348021