Search for Z′ bosons decaying to pairs of heavy Majorana neutrinos in proton-proton collisions at √s = 13 TeV

A search for the production of pairs of heavy Majorana neutrinos (Nℓ ) from the decays of Z′ bosons is performed using the CMS detector at the LHC. The data were collected in proton-proton collisions at a center-of-mass energy of √s = 13 TeV, with an integrated luminosity of 138 fb−1 . The signature...

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Detalles Bibliográficos
Autores: Tumasyan, Armen, Silveira, Gustavo Gil da, Bernardes, César Augusto, CMS Collaboration
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:Brasil
Institución:Universidade Federal do Rio Grande do Sul (UFRGS)
Repositorio:Repositório Institucional da UFRGS
Idioma:inglés
OAI Identifier:oai:www.lume.ufrgs.br:10183/278389
Acceso en línea:http://hdl.handle.net/10183/278389
Access Level:acceso abierto
Palabra clave:Aceleradores de partículas
Bosons Z
Colisões proton-proton
Beyond standard model
Hadron-Hadron scattering
Descripción
Sumario:A search for the production of pairs of heavy Majorana neutrinos (Nℓ ) from the decays of Z′ bosons is performed using the CMS detector at the LHC. The data were collected in proton-proton collisions at a center-of-mass energy of √s = 13 TeV, with an integrated luminosity of 138 fb−1 . The signature for the search is an excess in the invariant mass distribution of the fnal-state objects, two same-favor leptons (e or µ) and at least two jets. No signifcant excess of events beyond the expected background is observed. Upper limits at 95% confdence level are set on the product of the Z′ production cross section and its branching fraction to a pair of Nℓ , as functions of Nℓ and Z′ boson masses (mNℓ and mZ′, respectively) for mZ′ from 0.4 to 4.6 TeV and mNℓ from 0.1 TeV to mZ′/2. In the theoretical framework of a left-right symmetric model, exclusion bounds in the mNℓ -mZ′ plane are presented in both the electron and muon channels. The observed upper limit on mZ′ reaches up to 4.42 TeV. These are the most restrictive limits to date on the mass of Nℓ as a function of the Z′ boson mass.