EBookClubs

Read Books & Download eBooks Full Online

EBookClubs

Read Books & Download eBooks Full Online

Book Measurement of the Higgs Boson Properties Using Its Decay to a Pair of  tau  Leptons in Proton proton Collisions at    s

Download or read book Measurement of the Higgs Boson Properties Using Its Decay to a Pair of tau Leptons in Proton proton Collisions at s written by Doyeong Kim and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Compact Muon Solenoid (CMS) detector has successfully operated with the Large Hadron Collider (LHC) collisions since 2010, leading to the Higgs boson discovery in 2012 by the CMS and ATLAS collaborations. The analyses of data taken during Run 2 (2016-2018) has already led to many interesting results about the properties of the Higgs boson and for the most part they are compatible in the context of the standard model (SM) so far. These studies are important because the SM appears to be an approximation of a more general theory. Precise studies of the Higgs boson's interactions with the known matter and force particles are essential to reveal the microscopic deviations from the SM prediction. One of such interactions is Yukawa couplings of the Higgs boson and fermions. The H → [tau tau] decay is the most sensitive fermionic decay mode that allows direct probing of this interaction. This thesis presents a study of the Higgs boson properties by observing its decay to a pair of tau leptons and testing evidence of non-SM interactions in the Higgs boson production. The results exploit the data collected by the CMS detector during LHC Run-2, in proton-proton collisions with a center-of-mass energy of 13 TeV. Firstly, the Higgs bosons' properties were explored by two complementary approaches by measuring its cross sections. Thanks to the observation of the H → [tau tau] decay in 2016, we can measure the total cross section with higher precision. Furthermore, in the first analysis, the cross sections of different Higgs productions were scrutinized using fine selections within each Higgs production mode which are mutually exclusive using the Simplified Template Cross Section (STXS) framework, proposed by the LHC Higgs Cross Section Working Group. In the second analysis, the first-ever measurement of the inclusive and differential fiducial cross sections for the Higgs boson production decaying to a pair of tau leptons was presented. In the third analysis, a search for anomalous couplings in the Higgs production vertex, including Charge-Parity (CP) violating couplings, is also performed targeting Higgs boson production via gluon fusion in association with two jets and vector boson fusion. None of these analyses has found any hint of new physics beyond the SM, but stringent limits on anomalous Higgs boson couplings to data were set and cross sections of the Higgs bosons in smaller phase spaces were precisely measured.

Book Measurement of the Higgs boson Coupling to Tau leptons and Combined Measurements of Higgs boson Properties at  square Roots s

Download or read book Measurement of the Higgs boson Coupling to Tau leptons and Combined Measurements of Higgs boson Properties at square Roots s written by Théo J. Megy and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The measurement of the Higgs-boson coupling to tau-leptons, based on an integrated luminosity of 36.1 ifb recorded at a centre-of-mass energy of 13 TeV by the ATLAS detector, is presented in this thesis. The analysis considers all combinations of leptonic and hadronic decays of tau-leptons, and targets the main two production modes of the Higgs boson, gluon Fusion and Vector-Boson Fusion. The inclusive cross section of the H->tautau decay channel is measured as 3.77 +1.06-0.95 (+0.60-0.59 (Stat.) +0.87-0.74 (Syst.)) pb, which corresponds to a deviation from the background-only hypothesis with an observed (expected) significance of 4.4 (4.1) standard deviations. In addition, the measurement of cross sections in the framework of Simplified Template Cross Sections is discussed. All measurement are in agreement with predictions of the Standard Model. The combined measurement of Higgs-boson properties is also presented, based on up to 79.8 ifb of data recorded at sqrt(s) = 13 TeV by the ATLAS detector. An observation of the four main production modes (ggF, VBF, VH and ttH+tH) and of four of the five main decay channels (H->gammagamma, H->ZZ, H->WW and H->bb) of the Higgs boson is achieved. In particular, the deviation from the background-only hypothesis with an observed (expected) significance of 6.5 (5.3) standard deviations for the VBF production mode is the first observation of this process by a single experiment. Measurements in the scope of the kappa-framework and of Simplified Template Cross Sections are also discussed. All the performed measurements are compatible with the Standard-Model expectations.

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

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:

Book Measurement of the Higgs boson Coupling to Tau leptons and Combined Measurements of Higgs boson Properties at Sqrt s

Download or read book Measurement of the Higgs boson Coupling to Tau leptons and Combined Measurements of Higgs boson Properties at Sqrt s written by Théo Megy and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The measurement of the Higgs-boson coupling to tau-leptons, based on an integrated luminosity of 36.1 ifb recorded at a centre-of-mass energy of 13 TeV by the ATLAS detector, is presented in this thesis. The analysis considers all combinations of leptonic and hadronic decays of tau-leptons, and targets the main two production modes of the Higgs boson, gluon Fusion and Vector-Boson Fusion. The inclusive cross section of the H->tautau decay channel is measured as 3.77 +1.06-0.95 (+0.60-0.59 (Stat.) +0.87-0.74 (Syst.)) pb, which corresponds to a deviation from the background-only hypothesis with an observed (expected) significance of 4.4 (4.1) standard deviations. In addition, the measurement of cross sections in the framework of Simplified Template Cross Sections is discussed. All measurement are in agreement with predictions of the Standard Model. The combined measurement of Higgs-boson properties is also presented, based on up to 79.8 ifb of data recorded at sqrt(s) = 13 TeV by the ATLAS detector. An observation of the four main production modes (ggF, VBF, VH and ttH+tH) and of four of the five main decay channels (H->gammagamma, H->ZZ, H->WW and H->bb) of the Higgs boson is achieved. In particular, the deviation from the background-only hypothesis with an observed (expected) significance of 6.5 (5.3) standard deviations for the VBF production mode is the first observation of this process by a single experiment. Measurements in the scope of the kappa-framework and of Simplified Template Cross Sections are also discussed. All the performed measurements are compatible with the Standard-Model expectations

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

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.

Book Heavy Neutral Particle Decays to Tau Pairs

Download or read book Heavy Neutral Particle Decays to Tau Pairs written by Michail Bachtis and published by Springer. This book was released on 2016-08-27 with total page 0 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.

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

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

Book Measurements of Higgs Boson Properties in Proton Proton Collisions at    s  7  8 and 13 TeV at the CERN Large Hadron Collider

Download or read book Measurements of Higgs Boson Properties in Proton Proton Collisions at s 7 8 and 13 TeV at the CERN Large Hadron Collider written by Ulascan Sarica and published by Springer Nature. This book was released on 2019-09-26 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis documents the measurement of lifetime, width, mass, and couplings to two electroweak bosons of the recently-discovered Higgs boson using data from the CMS experiment at the Large Hadron Collider. Both on-shell (at the mass of around 125 GeV) and off-shell (above 200 GeV) Higgs boson production is studied and an excess of off-shell production with significance above two standard deviations is observed for the first time. The latter is a qualitative new way to study the Higgs field, responsible for generation of mass of all the known elementary particles. In addition, phenomenological tools have been developed with the Monte Carlo event generator and matrix element techniques for an optional analysis of LHC data. Optimization of the CMS data with careful alignment of the silicon tracker is also presented.

Book Search for Lepton Flavour Violating Decays of the Higgs Boson to E Tau and E Mu in Proton proton Collisions at Sqrt s

Download or read book Search for Lepton Flavour Violating Decays of the Higgs Boson to E Tau and E Mu 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 direct search for lepton flavour violating decays of the Higgs boson (H) in the H to e tau and H to e mu channels is described. The data sample used in the search was collected in proton-proton collisions at sqrt(s)=8 TeV with the CMS detector at the LHC and corresponds to an integrated luminosity of 19.7 inverse femtobarns. No evidence is found for lepton flavour violating decays in either final state. Upper limits on the branching fractions, B(H to e tau)

Book Measurements of the Higgs Boson Production and Decay Rates and Coupling Strengths Using  pp  Collision Data at  square Root  S

Download or read book Measurements of the Higgs Boson Production and Decay Rates and Coupling Strengths Using pp Collision Data at square Root S written by Fangzhou Zhang and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Search for Mono Higgs Boson to  tau  Pairs at the LHC with  squareroot s

Download or read book Search for Mono Higgs Boson to tau Pairs at the LHC with squareroot s written by Garrett Ned Funk and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for dark matter is performed using the proton-proton collision dataset recorded by the CMS detector at the CERN LHC during the data-taking period of 2016. The dataset corresponds to an integrated luminosity of 35.9 fb−1 of proton-proton collisions at 13 TeV. The search is performed for two theory models, both of which incorporate the standard model Higgs boson into dark matter production. The signature in both theory models is a standard model Higgs boson plus missing momentum from the dark matter, which does not interact with the CMS detector. This signature is dubbed 'mono-Higgs'. The first theory model uses an additional set of Higgs sector parameters and incorporates a new mediator particle and a pseudoscalar Higgs boson into dark matter production. The second model introduces a new mediator that carries baryon number symmetry. The analysis presented in this thesis is specifically focused on the final state with a standard model Higgs boson decay to [tau] leptons. A range of parameter space is excluded with 95% confidence for both models, and an advanced technique is used to extend the exclusion for a particular range of one model. In the first model, mediator masses between 700 and 1200 GeV are excluded for a pseudoscalar mass of 300 GeV and a dark matter mass of 100 GeV. In the second model, mediator masses up to 500 GeV are excluded for a dark matter mass of 1 GeV.

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

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:

Book A Search for the Charged Higgs Boson Decays of the Top Quark Using Hadronic Decays of the Tau Lepton in Proton antiproton Collisions at  square Root s

Download or read book A Search for the Charged Higgs Boson Decays of the Top Quark Using Hadronic Decays of the Tau Lepton in Proton antiproton Collisions at square Root s written by Leslie Stevan Groer and published by . This book was released on 1998 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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

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).

Book Measurement of the Transverse Momentum Spectrum of the Higgs Boson Produced in Pp Collisions at Sqrt s

Download or read book Measurement of the Transverse Momentum Spectrum of the Higgs Boson Produced in Pp 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: The cross section for Higgs boson production in pp collisions is studied using the H to WW decay mode, followed by leptonic decays of the W bosons to an oppositely charged electron-muon pair in the final state. The measurements are performed using data collected by the CMS experiment at the LHC at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.4 inverse-femtobarns. The Higgs boson transverse momentum (pT) is reconstructed using the lepton pair pT and missing pT. The differential cross section times branching fraction is measured as a function of the Higgs boson pT in a fiducial phase space defined to match the experimental acceptance in terms of the lepton kinematics and event topology. The production cross section times branching fraction in the fiducial phase space is measured to be 39 +/- 8 (stat) +/- 9 (syst) fb. The measurements are found to agree, within experimental uncertainties, with theoretical calculations based on the standard model.