Cross-section Measurements of the Higgs Boson Decaying Into a Pair of [tau]-leptons in Proton-proton Collisions at Root S

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Book Synopsis Cross-section Measurements of the Higgs Boson Decaying Into a Pair of [tau]-leptons in Proton-proton Collisions at Root S by : Anne Kathrin Becker

Download or read book Cross-section Measurements of the Higgs Boson Decaying Into a Pair of [tau]-leptons in Proton-proton Collisions at Root S written by Anne Kathrin Becker and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Measurement of the Higgs Boson Coupling to Tau Leptons in Proton-proton Collisions at [square Root]s

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Book Synopsis Measurement of the Higgs Boson Coupling to Tau Leptons in Proton-proton Collisions at [square Root]s by : Frank Sauerburger

Download or read book Measurement of the Higgs Boson Coupling to Tau Leptons in Proton-proton Collisions at [square Root]s written by Frank Sauerburger and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Cross Section Measurement and Search for New Physics with Top Quark Pair Events Involving a Tau Lepton in ATLAS

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ISBN 13 :
Total Pages : 336 pages
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Book Synopsis Cross Section Measurement and Search for New Physics with Top Quark Pair Events Involving a Tau Lepton in ATLAS by : Jennifer Lynn Godfrey

Download or read book Cross Section Measurement and Search for New Physics with Top Quark Pair Events Involving a Tau Lepton in ATLAS written by Jennifer Lynn Godfrey and published by . This book was released on 2013 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2011, the ATLAS detector recorded an integrated luminosity of over 5 fb−1 of proton-proton collisions delivered by the LHC at a centre-of-mass square root of s = 7 TeV. The first of two analyses is a test of the standard model and the world's most precise measurement of the top quark pair production cross section for final states which include a hadronically decaying tau lepton. The second analysis uses the same dataset to search for a charged Higgs boson, also resulting in the world's best limits for the search channel. In the cross section measurement, 2.1 fb−1 of ATLAS proton-proton collision data is used to measure the top quark pair production cross section in events containing an isolated electron or muon and a tau lepton decaying hadronically. After initial event requirements, the leading background comes from top quark pairs with jets faking tau leptons. A fit to a tau lepton identification variable is used to determine the signal yield. The measured cross section, [sigma][subscript{tt̄}] 186±13(stat.)±2019(syst.)±7(lumi.)pb, is in good agreement with the standard model prediction. Several extensions to the standard model predict the existence of at least one charged Higgs boson, H[superscript ±]. According to these extensions, the top quark can decay into a bottom quark and a light charged Higgs boson in addition to the standard model decay to a bottom quark and aW boson. In the second analysis, event yield ratios between different final states are measured using 4.6 fb−1 of ATLAS data. This is compared to simulation to search for a violation of lepton universality. This ratio-based method reduces the impact of systematic uncertainties in the analysis. No significant deviations from the standard model predictions are observed. With the assumption that the charged Higgs boson branching ratio to a tau lepton and a neutrino is 100%, upper limits in the range 3.2%-4.4% can be placed on the top quark to charged Higgs branching ratio for 90 less than or equal to m[subscript {H[superscript ±]}] less than or equal to 140 GeV. After combination with results from a search for charged Higgs bosons in tt̄ decays using the thad+jets final state, upper limits on this branching ratio can be set in the range 0.8%-3.4%, for 90 less than or equal to m[subscript {H[superscript ±]}] less than or equal to 140 GeV.

Search for the Higgs Boson Decaying to Two Tau Leptons in Proton-antiproton Collisions at a Center of Mass Energy of 1.96 TeV

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Book Synopsis Search for the Higgs Boson Decaying to Two Tau Leptons in Proton-antiproton Collisions at a Center of Mass Energy of 1.96 TeV by : Andrey Elagin

Download or read book Search for the Higgs Boson Decaying to Two Tau Leptons in Proton-antiproton Collisions at a Center of Mass Energy of 1.96 TeV written by Andrey Elagin and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for the Higgs boson decaying to tau tau using 7.8 fb^-1 of pp collisions at 1.96 TeV collected with CDF II detector is presented. The search is sensitive to four production mechanisms of the Higgs boson: ggH, WH, ZH and VBF. Modes where one tau decay leptonically, and another decay, hadronically, are considered. Two novel techniques are developed and used in the search. A Probabilistic Particle Flow Algorithm is used for energy measurements of the hadronic tau candidates. The signal is discriminated from backgrounds by the Missing Mass Calculator, which allows for full invariant mass reconstruction of tau tau pair. The data are found to be consistent with the background only hypothesis. Therefore a 95% confidence level upper limit on the Standard Model Higgs boson cross section was set. At M_H=120 GeV/c^2 observed limit is 14.9 x sigma_SM x Br(H -> tau tau).

Electroweak Physics and Evidence for a Higgs Boson Decaying to a Pair of Tau Leptons with the CMS Detector

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ISBN 13 :
Total Pages : 170 pages
Book Rating : 4.:/5 (1 download)

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Book Synopsis Electroweak Physics and Evidence for a Higgs Boson Decaying to a Pair of Tau Leptons with the CMS Detector by : Aram Apyan

Download or read book Electroweak Physics and Evidence for a Higgs Boson Decaying to a Pair of Tau Leptons with the CMS Detector written by Aram Apyan and published by . This book was released on 2017 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: .Studies of the electroweak interactions using final states with leptons in proton-proton collisions at the Large Hadron Collider at [square root of] s = 7 TeV, [square root of] s = 8 TeV, and [square root of] s = 13 TeV center-of-mass energies are described. Measurements of total inclusive and fiducial W and Z boson production cross sections and their ratios are performed. The W and Z bosons are observed via their decays to electrons and muons. An indirect determination of the total width of the W boson and the B(W --> lv) from the measured cross section ratios is described. The discovery of a new boson with a mass of 125 GeV at the Large Hadron Collider in 2012 sheds a new light on understanding the nature of electroweak symmetry breaking. A question of great significance is whether the new field couples to fermions through a Yukawa coupling interaction predicted in the standard model of particles. Evidence of the 125 GeV Higgs boson decay to a pair of tau leptons with an observed significance of 3.1 standard deviations is established. The nature of the Higgs sector is probed through searches for neutral resonances decaying to a pair of tau leptons in gluon-fusion and b-quark associated production modes with no observation of a significant excess. In addition, the feasibility of measuring the standard model Higgs boson self-coupling with an expected data sample corresponding to an integrated luminosity of 3000 fb-1 is studied.

Measurement of the Z --] [tau] [tau] Production Cross-section in Proton-proton Collisions at [square Root Of] S

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Total Pages : 137 pages
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Book Synopsis Measurement of the Z --] [tau] [tau] Production Cross-section in Proton-proton Collisions at [square Root Of] S by : Justin Griffiths

Download or read book Measurement of the Z --] [tau] [tau] Production Cross-section in Proton-proton Collisions at [square Root Of] S written by Justin Griffiths and published by . This book was released on 2012 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first measurement of the inclusive cross-section of the Z boson decaying to two tau leptons was measured with the ATLAS detector at the LHC. The data sample in this analysis represents an integrated luminosity of 35 pb ̄1 of proton-proton collisions at a center of mass energy of sqrt(s)=7 TeV. Separate measurements were performed in four decay modes based on how the two tau leptons decay: to hadrons and an electron, to hadrons and a muon, to an electron and a muon, and to two muons. In all four final states, inclusive cross-section measurements were made both in the fiducial region of the ATLAS detector where acceptance is high and in the full phase space, restricted to the mass range of [66, 116] GeV. The measurements from the four individual channels were then combined to yield the combined Z --> [tau] [tau] cross-section of 970 ± 70 (stat.) ± 60 (sys.) ± 30 (lumi.) pb.

Measurement of the Associated Production of a Higgs Boson Decaying Into B-quarks with a Vector Boson at High Transverse Momentum in Pp Collisions at [square Root]s

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Book Synopsis Measurement of the Associated Production of a Higgs Boson Decaying Into B-quarks with a Vector Boson at High Transverse Momentum in Pp Collisions at [square Root]s by : ATLAS Collaboration CERN

Download or read book Measurement of the Associated Production of a Higgs Boson Decaying Into B-quarks with a Vector Boson at High Transverse Momentum in Pp Collisions at [square Root]s written by ATLAS Collaboration CERN and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The associated production of a Higgs boson with a W or Z boson decaying into leptons and where the Higgs boson decays to a pair is measured in the high vector-boson transverse momentum regime, above 250 GeV, with the ATLAS detector. The analysed data, corresponding to an integrated luminosity of , were collected in proton-proton collisions at the Large Hadron Collider between 2015 and 2018 at a centre-of-mass energy of . The measured signal strength, defined as the ratio of the measured signal yield to that predicted by the Standard Model, is corresponding to an observed (expected) significance of 2.1 (2.7) standard deviations. Cross-sections of associated production of a Higgs boson decaying into b quark pairs with a W or Z gauge boson, decaying into leptons, are measured in two exclusive vector boson transverse momentum regions, 250-400 GeV and above 400 GeV, and interpreted as constraints on anomalous couplings in the framework of a Standard Model effective field theory

Measurements of Higgs Boson Production Cross-sections in the H -> [tau][plus][tau][minus] Decay Channel in Pp Collisions at [square Root]s

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Book Synopsis Measurements of Higgs Boson Production Cross-sections in the H -> [tau][plus][tau][minus] Decay Channel in Pp Collisions at [square Root]s by : ATLAS Collaboration CERN

Download or read book Measurements of Higgs Boson Production Cross-sections in the H -> [tau][plus][tau][minus] Decay Channel in Pp Collisions at [square Root]s written by ATLAS Collaboration CERN and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Heavy Neutral Particle Decays to Tau Pairs

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Publisher : Springer Science & Business Media
ISBN 13 : 3319032577
Total Pages : 161 pages
Book Rating : 4.3/5 (19 download)

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Book Synopsis Heavy Neutral Particle Decays to Tau Pairs by : Michail Bachtis

Download or read book Heavy Neutral Particle Decays to Tau Pairs written by Michail Bachtis and published by Springer Science & Business Media. This book was released on 2013-12-13 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work presented in this thesis spans a wide range of experimental particle physics subjects, starting from level-1 trigger electronics to the final results of the search for Higgs boson decay and to tau lepton pairs. The thesis describes an innovative reconstruction algorithm for tau decays and details how it was instrumental in providing a measurement of Z decay to tau lepton pairs. The reliability of the analysis is fully established by this measurement before the Higgs boson decay to tau lepton pairs is considered. The work described here continues to serve as a model for analysing CMS Higgs to tau leptons measurements.

Scientific and Technical Aerospace Reports

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ISBN 13 :
Total Pages : 704 pages
Book Rating : 4.X/5 (4 download)

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Book Synopsis Scientific and Technical Aerospace Reports by :

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Measurements of the Higgs Boson Inclusive and Differential Fiducial Cross-sections in the Diphoton Decay Channel with Pp Collisions at [square Root]s

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Total Pages : 0 pages
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Book Synopsis Measurements of the Higgs Boson Inclusive and Differential Fiducial Cross-sections in the Diphoton Decay Channel with Pp Collisions at [square Root]s by : [Study Group] ATLAS Collaboration CERN

Download or read book Measurements of the Higgs Boson Inclusive and Differential Fiducial Cross-sections in the Diphoton Decay Channel with Pp Collisions at [square Root]s written by [Study Group] ATLAS Collaboration CERN and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: A measurement of inclusive and differential fiducial cross-sections for the production of the Higgs boson decaying into two photons is performed using 139 fb−1 of proton-proton collision data recorded at s√ = 13 TeV by the ATLAS experiment at the Large Hadron Collider. The inclusive cross-section times branching ratio, in a fiducial region closely matching the experimental selection, is measured to be 67 ± 6 fb, which is in agreement with the state-of-the-art Standard Model prediction of 64 ± 4 fb. Extrapolating this result to the full phase space and correcting for the branching ratio, the total cross-section for Higgs boson production is estimated to be 58 ± 6 pb. In addition, the cross-sections in four fiducial regions sensitive to various Higgs boson production modes and differential cross-sections as a function of either one or two of several observables are measured. All the measurements are found to be in agreement with the Standard Model predictions. The measured transverse momentum distribution of the Higgs boson is used as an indirect probe of the Yukawa coupling of the Higgs boson to the bottom and charm quarks. In addition, five differential cross-section measurements are used to constrain anomalous Higgs boson couplings to vector bosons in the Standard Model effective field theory framework

Measurements of Production Cross Sections of the Higgs Boson in the Four-lepton Final State in Proton–proton Collisions at √s

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Book Synopsis Measurements of Production Cross Sections of the Higgs Boson in the Four-lepton Final State in Proton–proton Collisions at √s by : Albert M. Sirunyan

Download or read book Measurements of Production Cross Sections of the Higgs Boson in the Four-lepton Final State in Proton–proton Collisions at √s written by Albert M. Sirunyan and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Measurement of the Higgs Boson Decay to Τ-pairs in the Lepton Plus Hadrons Final State in Proton-proton Collisions with the ATLAS Detector

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Book Synopsis Measurement of the Higgs Boson Decay to Τ-pairs in the Lepton Plus Hadrons Final State in Proton-proton Collisions with the ATLAS Detector by : Jessica Kristina Liebal

Download or read book Measurement of the Higgs Boson Decay to Τ-pairs in the Lepton Plus Hadrons Final State in Proton-proton Collisions with the ATLAS Detector written by Jessica Kristina Liebal and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Particle Physics Reference Library

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Publisher : Springer Nature
ISBN 13 : 3030382079
Total Pages : 632 pages
Book Rating : 4.0/5 (33 download)

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Book Synopsis Particle Physics Reference Library by : Herwig Schopper

Download or read book Particle Physics Reference Library written by Herwig Schopper and published by Springer Nature. This book was released on 2020 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first open access volume of the handbook series contains articles on the standard model of particle physics, both from the theoretical and experimental perspective. It also covers related topics, such as heavy-ion physics, neutrino physics and searches for new physics beyond the standard model. A joint CERN-Springer initiative, the "Particle Physics Reference Library" provides revised and updated contributions based on previously published material in the well-known Landolt-Boernstein series on particle physics, accelerators and detectors (volumes 21A, B1,B2,C), which took stock of the field approximately one decade ago. Central to this new initiative is publication under full open access

Measurements of ZH and WH Production in the H → Bb Decay Channel in Pp Collisions at 13 TeV with the ATLAS Detector

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Book Synopsis Measurements of ZH and WH Production in the H → Bb Decay Channel in Pp Collisions at 13 TeV with the ATLAS Detector by : ATLAS Collaboration CERN

Download or read book Measurements of ZH and WH Production in the H → Bb Decay Channel in Pp Collisions at 13 TeV with the ATLAS Detector written by ATLAS Collaboration CERN and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Measurements are presented of the Standard Model Higgs boson decaying into a bb ̄ pair and produced in association with a W or Z boson decaying into leptons, using proton-proton collision data collected between 2015 and 2018 by the ATLAS detector. The measurements use data delivered by the Large Hadron Collider at a centre-of-mass energy of s√=13 TeV, corresponding to an integrated luminosity of 139 fb−1. The production of a Higgs boson in association with a W or Z boson is established, with observed (expected) significances of 4.0 (4.1) and 5.3 (5.1) standard deviations, respectively. Cross-sections of associated production of a Higgs boson decaying into bottom quark pairs with an electroweak gauge boson, W or Z, decaying into leptons are measured as a function of the gauge boson transverse momentum in kinematic fiducial volumes. The cross-section measurements are all consistent with the Standard Model expectations, and the total uncertainties vary from 30% in the high gauge boson transverse momentum regions to 85% in the low regions

Higgs Boson Decays into a Pair of Bottom Quarks

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Publisher : Springer Nature
ISBN 13 : 3030879380
Total Pages : 171 pages
Book Rating : 4.0/5 (38 download)

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Book Synopsis Higgs Boson Decays into a Pair of Bottom Quarks by : Cecilia Tosciri

Download or read book Higgs Boson Decays into a Pair of Bottom Quarks written by Cecilia Tosciri and published by Springer Nature. This book was released on 2021-10-22 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: The discovery in 2012 of the Higgs boson at the Large Hadron Collider (LHC) represents a milestone for the Standard Model (SM) of particle physics. Most of the SM Higgs production and decay rates have been measured at the LHC with increased precision. However, despite its experimental success, the SM is known to be only an effective manifestation of a more fundamental description of nature. The scientific research at the LHC is strongly focused on extending the SM by searching, directly or indirectly, for indications of New Physics. The extensive physics program requires increasingly advanced computational and algorithmic techniques. In the last decades, Machine Learning (ML) methods have made a prominent appearance in the field of particle physics, and promise to address many challenges faced by the LHC. This thesis presents the analysis that led to the observation of the SM Higgs boson decay into pairs of bottom quarks. The analysis exploits the production of a Higgs boson associated with a vector boson whose signatures enable efficient triggering and powerful background reduction. The main strategy to maximise the signal sensitivity is based on a multivariate approach. The analysis is performed on a dataset corresponding to a luminosity of 79.8/fb collected by the ATLAS experiment during Run-2 at a centre-of-mass energy of 13 TeV. An excess of events over the expected background is found with an observed (expected) significance of 4.9 (4.3) standard deviation. A combination with results from other \Hbb searches provides an observed (expected) significance of 5.4 (5.5). The corresponding ratio between the signal yield and the SM expectation is 1.01 +- 0.12 (stat.)+ 0.16-0.15(syst.). The 'observation' analysis was further extended to provide a finer interpretation of the V H(H → bb) signal measurement. The cross sections for the VH production times the H → bb branching ratio have been measured in exclusive regions of phase space. These measurements are used to search for possible deviations from the SM with an effective field theory approach, based on anomalous couplings of the Higgs boson. The results of the cross-section measurements, as well as the constraining of the operators that affect the couplings of the Higgs boson to the vector boson and the bottom quarks, have been documented and discussed in this thesis. This thesis also describes a novel technique for the fast simulation of the forward calorimeter response, based on similarity search methods. Such techniques constitute a branch of ML and include clustering and indexing methods that enable quick and efficient searches for vectors similar to each other. The new simulation approach provides optimal results in terms of detector resolution response and reduces the computational requirements of a standard particles simulation.

Search for Heavy Resonances Decaying to Tau Lepton Pairs in Proton-proton Collisions at $\sqrt{s}$

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Book Synopsis Search for Heavy Resonances Decaying to Tau Lepton Pairs in Proton-proton Collisions at $\sqrt{s}$ by :

Download or read book Search for Heavy Resonances Decaying to Tau Lepton Pairs in Proton-proton Collisions at $\sqrt{s}$ written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for heavy resonances that decay to tau lepton pairs is performed using proton-proton collisions at \sqrt{s}$ = 13 TeV. The data were collected with the CMS detector at the CERN LHC and correspond to an integrated luminosity of 2.2 inverse femtobarns. The observations are in agreement with standard model predictions. An upper limit at 95% confidence level on the product of the production cross section and branching fraction into tau lepton pairs is calculated as a function of the resonance mass. For the sequential standard model, the presence of Z' bosons decaying into tau lepton pairs is excluded for Z' masses below 2.1 TeV, extending previous limits for this final state. For the topcolor-assisted technicolor model, which predicts Z' bosons that preferentially couple to third-generation fermions, Z' masses below 1.7 TeV are excluded, representing the most stringent limit to date.