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Search for di-Higgs production to the $b\overline{b}\tau^{+}\tau^{-}$ final state using Support Vector Machines with the ATLAS detector at the Large Hadron Collider in $pp$ collisions at $\sqrt{s}=13\textrm{TeV}$

This thesis presents a search for resonant and standard model non-resonant di-Higgs production in the $b\overline{b}\tau^{+}\tau^{-}$ decay channel, with the semi-leptonic di-tau state. The search uses data collected by the ATLAS experiment at the LHC of $pp$-collisions at $\sqrt{s}=13\textrm{TeV}$...

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Detalles Bibliográficos
Autor principal: Stevenson, Thomas James
Lenguaje:eng
Publicado: 2018
Materias:
Acceso en línea:http://cds.cern.ch/record/2634914
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author Stevenson, Thomas James
author_facet Stevenson, Thomas James
author_sort Stevenson, Thomas James
collection CERN
description This thesis presents a search for resonant and standard model non-resonant di-Higgs production in the $b\overline{b}\tau^{+}\tau^{-}$ decay channel, with the semi-leptonic di-tau state. The search uses data collected by the ATLAS experiment at the LHC of $pp$-collisions at $\sqrt{s}=13\textrm{TeV}$ during 2015 and 2016, corresponding to an instantaneous luminosity of $36.1\,\mathrm{fb^{-1}}$. No deviation from the Standard Model prediction is observed. For the non-resonant standard model di-Higgs production an upper limit is set on the cross-section compared to the Standard Model prediction, $\frac{\sigma}{\sigma_{\textrm{SM}}}<24.44\;@\;95\% \textrm{CL}$. Upper limits are set on the cross-section times branching ratio for the resonant searches, where the results are interpreted in terms of constraints on a 2HDM heavy scalar Higgs model and a Randall-Sundrum Kaluza-Klein graviton model. The use of Support Vector Machines is investigated and benchmarked against the nominal results of the Boosted Decision Tree multivariate analysis, in pursuit of potential future improvements.
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institution Organización Europea para la Investigación Nuclear
language eng
publishDate 2018
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spelling cern-26349142019-09-30T06:29:59Zhttp://cds.cern.ch/record/2634914engStevenson, Thomas JamesSearch for di-Higgs production to the $b\overline{b}\tau^{+}\tau^{-}$ final state using Support Vector Machines with the ATLAS detector at the Large Hadron Collider in $pp$ collisions at $\sqrt{s}=13\textrm{TeV}$Particle Physics - ExperimentThis thesis presents a search for resonant and standard model non-resonant di-Higgs production in the $b\overline{b}\tau^{+}\tau^{-}$ decay channel, with the semi-leptonic di-tau state. The search uses data collected by the ATLAS experiment at the LHC of $pp$-collisions at $\sqrt{s}=13\textrm{TeV}$ during 2015 and 2016, corresponding to an instantaneous luminosity of $36.1\,\mathrm{fb^{-1}}$. No deviation from the Standard Model prediction is observed. For the non-resonant standard model di-Higgs production an upper limit is set on the cross-section compared to the Standard Model prediction, $\frac{\sigma}{\sigma_{\textrm{SM}}}<24.44\;@\;95\% \textrm{CL}$. Upper limits are set on the cross-section times branching ratio for the resonant searches, where the results are interpreted in terms of constraints on a 2HDM heavy scalar Higgs model and a Randall-Sundrum Kaluza-Klein graviton model. The use of Support Vector Machines is investigated and benchmarked against the nominal results of the Boosted Decision Tree multivariate analysis, in pursuit of potential future improvements.CERN-THESIS-2018-119oai:cds.cern.ch:26349142018-08-20T09:09:00Z
spellingShingle Particle Physics - Experiment
Stevenson, Thomas James
Search for di-Higgs production to the $b\overline{b}\tau^{+}\tau^{-}$ final state using Support Vector Machines with the ATLAS detector at the Large Hadron Collider in $pp$ collisions at $\sqrt{s}=13\textrm{TeV}$
title Search for di-Higgs production to the $b\overline{b}\tau^{+}\tau^{-}$ final state using Support Vector Machines with the ATLAS detector at the Large Hadron Collider in $pp$ collisions at $\sqrt{s}=13\textrm{TeV}$
title_full Search for di-Higgs production to the $b\overline{b}\tau^{+}\tau^{-}$ final state using Support Vector Machines with the ATLAS detector at the Large Hadron Collider in $pp$ collisions at $\sqrt{s}=13\textrm{TeV}$
title_fullStr Search for di-Higgs production to the $b\overline{b}\tau^{+}\tau^{-}$ final state using Support Vector Machines with the ATLAS detector at the Large Hadron Collider in $pp$ collisions at $\sqrt{s}=13\textrm{TeV}$
title_full_unstemmed Search for di-Higgs production to the $b\overline{b}\tau^{+}\tau^{-}$ final state using Support Vector Machines with the ATLAS detector at the Large Hadron Collider in $pp$ collisions at $\sqrt{s}=13\textrm{TeV}$
title_short Search for di-Higgs production to the $b\overline{b}\tau^{+}\tau^{-}$ final state using Support Vector Machines with the ATLAS detector at the Large Hadron Collider in $pp$ collisions at $\sqrt{s}=13\textrm{TeV}$
title_sort search for di-higgs production to the $b\overline{b}\tau^{+}\tau^{-}$ final state using support vector machines with the atlas detector at the large hadron collider in $pp$ collisions at $\sqrt{s}=13\textrm{tev}$
topic Particle Physics - Experiment
url http://cds.cern.ch/record/2634914
work_keys_str_mv AT stevensonthomasjames searchfordihiggsproductiontotheboverlinebtautaufinalstateusingsupportvectormachineswiththeatlasdetectoratthelargehadroncolliderinppcollisionsatsqrts13textrmtev