Search for a new scalar resonance in flavour-changing neutral-current top-quark decays t → qX (q = u, c), with X → bb¯ , in proton-proton collisions at √s = 13 TeV with the ATLAS detector

Detalhes bibliográficos
Autor(a) principal: Castro, Nuno Filipe
Data de Publicação: 2023
Outros Autores: Onofre, A., ATLAS Collaboration
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
Texto Completo: https://hdl.handle.net/1822/87862
Resumo: A search for flavour-changing neutral-current decays of a top quark into an up-type quark (either up or charm) and a light scalar particle X decaying into a bottom anti-bottom quark pair is presented. The search focuses on top-quark pair production where one top quark decays to qX, with X → bb¯ , and the other top quark decays according to the Standard Model, with the W boson decaying leptonically. The final state is thus characterised by an isolated electron or muon and at least four jets. Events are categorised according to the multiplicity of jets and jets tagged as originating from b-quarks, and a neural network is used to discriminate between signal and background processes. The data analysed correspond to 139 fb −1 of proton–proton collisions at a centre-of-mass energy of 13 TeV, recorded with the ATLAS detector at the LHC. The 95% confidence-level upper limits between 0.019% and 0.062% are derived for the branching fraction B (t → uX) and between 0.018% and 0.078% for the branching fraction B (t → cX), for masses of the scalar particle X between 20 and 160 GeV. [Figure not available: see fulltext.]
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spelling Search for a new scalar resonance in flavour-changing neutral-current top-quark decays t → qX (q = u, c), with X → bb¯ , in proton-proton collisions at √s = 13 TeV with the ATLAS detectorHadron-Hadron ScatteringCiências Naturais::Ciências FísicasA search for flavour-changing neutral-current decays of a top quark into an up-type quark (either up or charm) and a light scalar particle X decaying into a bottom anti-bottom quark pair is presented. The search focuses on top-quark pair production where one top quark decays to qX, with X → bb¯ , and the other top quark decays according to the Standard Model, with the W boson decaying leptonically. The final state is thus characterised by an isolated electron or muon and at least four jets. Events are categorised according to the multiplicity of jets and jets tagged as originating from b-quarks, and a neural network is used to discriminate between signal and background processes. The data analysed correspond to 139 fb −1 of proton–proton collisions at a centre-of-mass energy of 13 TeV, recorded with the ATLAS detector at the LHC. The 95% confidence-level upper limits between 0.019% and 0.062% are derived for the branching fraction B (t → uX) and between 0.018% and 0.078% for the branching fraction B (t → cX), for masses of the scalar particle X between 20 and 160 GeV. [Figure not available: see fulltext.]USDOE -U.S. Department of Energy(IN2P3-CNRS)info:eu-repo/semantics/publishedVersionSpringerUniversidade do MinhoCastro, Nuno FilipeOnofre, A.ATLAS Collaboration20232023-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttps://hdl.handle.net/1822/87862engAad, G., Abbott, B., Abbott, D. C., Abeling, K., Abidi, S. H., Aboulhorma, A., . . . Collaboration, A. (2023). Search for a new scalar resonance in flavour-changing neutral-current top-quark decays <i>t</i> → <i>qX</i> (<i>q</i> = <i>u</i>, <i>c</i>), with <i>X</i> → <i>b</i>(<i>b</i>)over-bar, in proton-proton collisions at √<i>s</i>=13 TeV with the ATLAS detector. Journal of High Energy Physics(7). doi: 10.1007/jhep07(2023)1991126-67081029-847910.1007/jhep07(2023)199https://link.springer.com/article/10.1007/JHEP07(2023)199info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2024-05-11T04:38:54Zoai:repositorium.sdum.uminho.pt:1822/87862Portal AgregadorONGhttps://www.rcaap.pt/oai/openairemluisa.alvim@gmail.comopendoar:71602024-05-11T04:38:54Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse
dc.title.none.fl_str_mv Search for a new scalar resonance in flavour-changing neutral-current top-quark decays t → qX (q = u, c), with X → bb¯ , in proton-proton collisions at √s = 13 TeV with the ATLAS detector
title Search for a new scalar resonance in flavour-changing neutral-current top-quark decays t → qX (q = u, c), with X → bb¯ , in proton-proton collisions at √s = 13 TeV with the ATLAS detector
spellingShingle Search for a new scalar resonance in flavour-changing neutral-current top-quark decays t → qX (q = u, c), with X → bb¯ , in proton-proton collisions at √s = 13 TeV with the ATLAS detector
Castro, Nuno Filipe
Hadron-Hadron Scattering
Ciências Naturais::Ciências Físicas
title_short Search for a new scalar resonance in flavour-changing neutral-current top-quark decays t → qX (q = u, c), with X → bb¯ , in proton-proton collisions at √s = 13 TeV with the ATLAS detector
title_full Search for a new scalar resonance in flavour-changing neutral-current top-quark decays t → qX (q = u, c), with X → bb¯ , in proton-proton collisions at √s = 13 TeV with the ATLAS detector
title_fullStr Search for a new scalar resonance in flavour-changing neutral-current top-quark decays t → qX (q = u, c), with X → bb¯ , in proton-proton collisions at √s = 13 TeV with the ATLAS detector
title_full_unstemmed Search for a new scalar resonance in flavour-changing neutral-current top-quark decays t → qX (q = u, c), with X → bb¯ , in proton-proton collisions at √s = 13 TeV with the ATLAS detector
title_sort Search for a new scalar resonance in flavour-changing neutral-current top-quark decays t → qX (q = u, c), with X → bb¯ , in proton-proton collisions at √s = 13 TeV with the ATLAS detector
author Castro, Nuno Filipe
author_facet Castro, Nuno Filipe
Onofre, A.
ATLAS Collaboration
author_role author
author2 Onofre, A.
ATLAS Collaboration
author2_role author
author
dc.contributor.none.fl_str_mv Universidade do Minho
dc.contributor.author.fl_str_mv Castro, Nuno Filipe
Onofre, A.
ATLAS Collaboration
dc.subject.por.fl_str_mv Hadron-Hadron Scattering
Ciências Naturais::Ciências Físicas
topic Hadron-Hadron Scattering
Ciências Naturais::Ciências Físicas
description A search for flavour-changing neutral-current decays of a top quark into an up-type quark (either up or charm) and a light scalar particle X decaying into a bottom anti-bottom quark pair is presented. The search focuses on top-quark pair production where one top quark decays to qX, with X → bb¯ , and the other top quark decays according to the Standard Model, with the W boson decaying leptonically. The final state is thus characterised by an isolated electron or muon and at least four jets. Events are categorised according to the multiplicity of jets and jets tagged as originating from b-quarks, and a neural network is used to discriminate between signal and background processes. The data analysed correspond to 139 fb −1 of proton–proton collisions at a centre-of-mass energy of 13 TeV, recorded with the ATLAS detector at the LHC. The 95% confidence-level upper limits between 0.019% and 0.062% are derived for the branching fraction B (t → uX) and between 0.018% and 0.078% for the branching fraction B (t → cX), for masses of the scalar particle X between 20 and 160 GeV. [Figure not available: see fulltext.]
publishDate 2023
dc.date.none.fl_str_mv 2023
2023-01-01T00:00:00Z
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv https://hdl.handle.net/1822/87862
url https://hdl.handle.net/1822/87862
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv Aad, G., Abbott, B., Abbott, D. C., Abeling, K., Abidi, S. H., Aboulhorma, A., . . . Collaboration, A. (2023). Search for a new scalar resonance in flavour-changing neutral-current top-quark decays <i>t</i> → <i>qX</i> (<i>q</i> = <i>u</i>, <i>c</i>), with <i>X</i> → <i>b</i>(<i>b</i>)over-bar, in proton-proton collisions at √<i>s</i>=13 TeV with the ATLAS detector. Journal of High Energy Physics(7). doi: 10.1007/jhep07(2023)199
1126-6708
1029-8479
10.1007/jhep07(2023)199
https://link.springer.com/article/10.1007/JHEP07(2023)199
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Springer
publisher.none.fl_str_mv Springer
dc.source.none.fl_str_mv reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
instacron:RCAAP
instname_str Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
instacron_str RCAAP
institution RCAAP
reponame_str Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
collection Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
repository.name.fl_str_mv Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
repository.mail.fl_str_mv mluisa.alvim@gmail.com
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