Light Higgs searches in t(t)over-bar phi production at the LHC
Autor(a) principal: | |
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Data de Publicação: | 2021 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10400.21/13277 |
Resumo: | In this paper we propose a new reconstruction method to explore the low mass region in the associated production of top-quark pairs (t (t) over bar) with a generic scalar boson (phi) at the LHC. The new method of mass reconstruction shows an improved resolution of at least a factor of two in the low mass region when compared to previous methods, without the loss of sensitivity of previous analyses. It turns out that it also leads to an improvement of the mass reconstruction of the 125 GeV Higgs for the same production process. We use an effective Lagrangian to describe a scalar with a generic Yukawa coupling to the top quarks. A full phenomenological analysis was performed, using Standard Model background and signal events generated with MadGraph5_aMC@NLO and reconstructed using a kinematic fit. The use of CP-sensitive variables allows then to maximize the distinction between CP-even and CP-odd components of the Yukawa couplings. Confidence Levels (CLs) for the exclusion of phi bosons with mixed CP (both CP-even and CP-odd components) were determined as a function of the top Yukawa couplings to the phi boson. The mass range analysed starts slightly above the Upsilon mass up to 40 GeV, although the analysis can be used for an arbitrary mass. If no new light scalar is found, exclusion limits at 95% CL for the absolute value of the CP-even and CP-odd Yukawa are derived. Finally, we analyse how these limits constrain the parameter space of the complex two-Higgs doublet model (C2HDM). |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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7160 |
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Light Higgs searches in t(t)over-bar phi production at the LHCBeyond Standard ModelCP violationIn this paper we propose a new reconstruction method to explore the low mass region in the associated production of top-quark pairs (t (t) over bar) with a generic scalar boson (phi) at the LHC. The new method of mass reconstruction shows an improved resolution of at least a factor of two in the low mass region when compared to previous methods, without the loss of sensitivity of previous analyses. It turns out that it also leads to an improvement of the mass reconstruction of the 125 GeV Higgs for the same production process. We use an effective Lagrangian to describe a scalar with a generic Yukawa coupling to the top quarks. A full phenomenological analysis was performed, using Standard Model background and signal events generated with MadGraph5_aMC@NLO and reconstructed using a kinematic fit. The use of CP-sensitive variables allows then to maximize the distinction between CP-even and CP-odd components of the Yukawa couplings. Confidence Levels (CLs) for the exclusion of phi bosons with mixed CP (both CP-even and CP-odd components) were determined as a function of the top Yukawa couplings to the phi boson. The mass range analysed starts slightly above the Upsilon mass up to 40 GeV, although the analysis can be used for an arbitrary mass. If no new light scalar is found, exclusion limits at 95% CL for the absolute value of the CP-even and CP-odd Yukawa are derived. Finally, we analyse how these limits constrain the parameter space of the complex two-Higgs doublet model (C2HDM).SpringerRCIPLAzevedo, DuarteCapucha, RodrigoGouveia, EmanuelOnofre, AntonioSantos, Rui2021-05-04T11:19:22Z2021-04-092021-04-09T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/10400.21/13277engAZEVEDO, Duarte; [et al] – Light Higgs searches in t(t)over-bar phi production at the LHC. Journal of High Energy Physics. ISSN 1029-8479. Vol. 2021, N.º 4 (2021), pp. 1-221029-847910.1007/JHEP04(2021)077info: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:RCAAP2023-08-03T10:07:45Zoai:repositorio.ipl.pt:10400.21/13277Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T20:21:15.525699Repositório 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 |
Light Higgs searches in t(t)over-bar phi production at the LHC |
title |
Light Higgs searches in t(t)over-bar phi production at the LHC |
spellingShingle |
Light Higgs searches in t(t)over-bar phi production at the LHC Azevedo, Duarte Beyond Standard Model CP violation |
title_short |
Light Higgs searches in t(t)over-bar phi production at the LHC |
title_full |
Light Higgs searches in t(t)over-bar phi production at the LHC |
title_fullStr |
Light Higgs searches in t(t)over-bar phi production at the LHC |
title_full_unstemmed |
Light Higgs searches in t(t)over-bar phi production at the LHC |
title_sort |
Light Higgs searches in t(t)over-bar phi production at the LHC |
author |
Azevedo, Duarte |
author_facet |
Azevedo, Duarte Capucha, Rodrigo Gouveia, Emanuel Onofre, Antonio Santos, Rui |
author_role |
author |
author2 |
Capucha, Rodrigo Gouveia, Emanuel Onofre, Antonio Santos, Rui |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
RCIPL |
dc.contributor.author.fl_str_mv |
Azevedo, Duarte Capucha, Rodrigo Gouveia, Emanuel Onofre, Antonio Santos, Rui |
dc.subject.por.fl_str_mv |
Beyond Standard Model CP violation |
topic |
Beyond Standard Model CP violation |
description |
In this paper we propose a new reconstruction method to explore the low mass region in the associated production of top-quark pairs (t (t) over bar) with a generic scalar boson (phi) at the LHC. The new method of mass reconstruction shows an improved resolution of at least a factor of two in the low mass region when compared to previous methods, without the loss of sensitivity of previous analyses. It turns out that it also leads to an improvement of the mass reconstruction of the 125 GeV Higgs for the same production process. We use an effective Lagrangian to describe a scalar with a generic Yukawa coupling to the top quarks. A full phenomenological analysis was performed, using Standard Model background and signal events generated with MadGraph5_aMC@NLO and reconstructed using a kinematic fit. The use of CP-sensitive variables allows then to maximize the distinction between CP-even and CP-odd components of the Yukawa couplings. Confidence Levels (CLs) for the exclusion of phi bosons with mixed CP (both CP-even and CP-odd components) were determined as a function of the top Yukawa couplings to the phi boson. The mass range analysed starts slightly above the Upsilon mass up to 40 GeV, although the analysis can be used for an arbitrary mass. If no new light scalar is found, exclusion limits at 95% CL for the absolute value of the CP-even and CP-odd Yukawa are derived. Finally, we analyse how these limits constrain the parameter space of the complex two-Higgs doublet model (C2HDM). |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-05-04T11:19:22Z 2021-04-09 2021-04-09T00:00:00Z |
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 |
http://hdl.handle.net/10400.21/13277 |
url |
http://hdl.handle.net/10400.21/13277 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
AZEVEDO, Duarte; [et al] – Light Higgs searches in t(t)over-bar phi production at the LHC. Journal of High Energy Physics. ISSN 1029-8479. Vol. 2021, N.º 4 (2021), pp. 1-22 1029-8479 10.1007/JHEP04(2021)077 |
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 |
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1799133483106304000 |