Download or read book Measurement of Higgs boson Production Cross sections and Test of CP Invariance in Vector boson Fusion Production in the H Lep Had Decay Mode with the ATLAS Detector written by Dirk Sammel and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of Higgs boson Production Cross sections and Test of CP Invariance in Vector boson Fusion Production in the H Lep Had Decay Mode with the ATLAS Detector written by Dirk Sammel and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: This thesis presents a measurement of the Higgs-boson production cross-section and a test of CP invariance in vector-boson fusion production in the semileptonic final state of the H->tau tau decay channel. Both analyses use proton-proton collision data corresponding to an integrated luminosity of 36.1 fb^-1 recorded with the ATLAS detector at a center-of-mass energy of 13 TeV. The events are divided into categories that target the specific kinematics of the gluon fusion- and the vector-boson fusion production processes of the Higgs boson. A maximum-likelihood fit in the reconstructed di-tau mass is performed to extract the H->tau tau cross-section. A signal excess with an observed significance of 2.4 standard deviations is found under the background-only hypothesis, whereas the expected significance is 2.6 standard deviations. The resulting H->tau tau cross-section is 3.13 +1.53/-1.33 pb, which is in agreement with the prediction by the Standard Model. In combination with the fully leptonic- and fully hadronic final states of the H->tau tau decay channel, the resulting cross-section is 3.77 +1.06/-0.95 pb, which is again consistent with the prediction by the Standard Model. The obtained observed significance is 4.4 standard deviations with an expected significance of 4.1 standard deviations. Further combination with the result of the search for the H->tau tau decay with data recorded at center-of-mass energies of 7 and 8 TeV yields an observed significance of 6.4 standard deviation with an expected significance of 5.4 standard deviations. To test CP invariance in the coupling between the Higgs boson and the electroweak gauge bosons, the production of the Higgs boson via vector-boson fusion is studied. This production process is separated from other processes by using a machine learning approach in form of Boosted Decision Trees. An Effective Field Theory approach is used to expand the Lagrangian of the Standard Model with additional CP-odd terms, quantified by the parameter dtilde. Maximum-likelihood fits are performed in the CP-odd Optimal Observable to set constraints on dtilde. The observed confidence interval at 68.3% confidence level is [-0.006,0.089], whereas the expected confidence interval is [-0.064,0.065]. The combination with the fully leptonic- and fully hadronic final states of the H->tau tau decay channel yields an observed 68.3% confidence interval of [-0.090,0.035] with an expected confidence interval of [-0.035,0.033]. In the combination, also an expected confidence interval at 95% confidence level of [-0.21,015] is obtained. All the results are in agreement with dtilde=0 as predicted by the Standard Model
Download or read book Measurement of the Higgs boson Production Cross section and Test of CP Invariance in Vector Boson Fusion Production with H Decays in the Fully leptonic Final State with the ATLAS Detector at the LHC written by Alena Lösle and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Test of CP Invariance in Vector boson Fusion Production of the Higgs Boson Using the Optimal Observable Method in the Ditau Decay Channel with the ATLAS Detector written by Hannah Arnold and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Test of CP invariance in Vector Boson Fusion Production of the Higgs Boson Using the Optimal Observable Method in the Di tau Decay Channel with the ATLAS Detector written by Martin Spangenberg (Researcher in particle physics) and published by . This book was released on 2016 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Test of CP Invariance in Vector boson Fusion Production of the Higgs Boson in the H tau tau Channel in Proton proton Collisions at S written by [Study Group] ATLAS Collaboration CERN and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: A test of CP invariance in Higgs boson production via vector-boson fusion is performed in the decay channel. This test uses the Optimal Observable method and is carried out using of proton-proton collision data collected by the ATLAS experiment at the LHC. Contributions from CP-violating interactions between the Higgs boson and electroweak gauge bosons are described by an effective field theory, in which the parameter governs the strength of CP violation. No sign of CP violation is observed in the distributions of the Optimal Observable, and is constrained to the interval [−0.090, 0.035] at the 68% confidence level (CL), compared to an expected interval of based upon the Standard Model prediction. No constraints can be set on at 95% CL, while an expected 95% CL interval of for the Standard Model hypothesis was expected
Download or read book Fiducial and Differential Cross section Measurements for the Vector boson fusion Production of the Higgs Boson in the H WW e Decay Channel at 13 TeV with the ATLAS Detector written by [Study Group] ATLAS Collaboration CERN and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Search for the Standard Model Higgs Boson and Test of CP Invariance in Vector boson Fusion Production of the Higgs Boson in the Fully Leptonic H t t L l 4v Final State in Proton proton Collisions with the ATLAS Detector at the LHC written by Christian Schillo and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of Higgs Boson Production Via Gluon Fusion and Vector boson Fusion in the H WW Decay Mode with the ATLAS Experiment at the LHC at square Root s written by Ralf Gugel and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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:
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
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.
Download or read book Measurements of Gluon gluon Fusion and Vector boson Fusion Higgs Boson Production Cross sections in the H WW E ny my ny Decay Channel in Pp Collisions at square 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:
Download or read book Measurement of GgF and VBF Higgs Boson Production Cross sections in the H WW evmv Decay Channel from Pp Collisions Collected with the ATLAS Detector at the LHC written by David Richard Shope and published by . This book was released on 2019 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observation and Measurement of Higgs Boson Decays to WW with the ATLAS Detector written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the observation of Higgs boson decays to WW* based on an excess over background of 6.1 standard deviations in the dilepton final state, where the Standard Model expectation is 5.8 standard deviations. Evidence for the vector-boson fusion (VBF) production process is obtained with a significance of 3.2 standard deviations. The results are obtained from a data sample corresponding to an integrated luminosity of 25 fb-1 from [arrow]"=7 and 8 TeV pp collisions recorded by the ATLAS detector at the LHC. For a Higgs boson mass of 125.36 GeV, the ratio of the measured value to the expected value of the total production cross section times branching fraction is 1.09+0.16-0.15(stat)+0.17-0.14(syst). The corresponding ratios for the gluon fusion and vector-boson fusion production mechanisms are 1.02 " 0.19(stat)+0.22-0.18(syst) and 1.27+0.44-0.40(stat)+0.30-0.21(syst), respectively. At [arrow]"=8 TeV, the total production cross sections are measured to be [sigma](gg 2!>H 2!WW*)=4.6"0.9(stat)+0.8-0.7(syst) pb and [sigma](VBF H 2!W*)=0.51+0.17-0.15(stat)+0.13-0.08(syst) pb. The fiducial cross section is determined for the gluon-fusion process in exclusive final states with 0 or one associated jet.
Download or read book Measurements of the Total and Differential Higgs Boson Production Cross Sections Combining the H 2 gamma gamma and H 2 ZZ 2 4l Decay Channels at arrow written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3 fb-1 of pp collisions produced by the Large Hadron Collider at a center-of-mass energy of [arrow]" = 8 TeV and recorded by the ATLAS detector. Cross sections are obtained from measured H 2![gamma][gamma] and H 2!ZZ* 2!4l event yields, which are combined accounting for detector efficiencies, fiducial acceptances, and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be [sigma]pp2! = 33.0 " 5.3 (stat) " 1.6 (syst) pb. The measurements are compared to state-of-the-art predictions.
Download or read book Measurements of the Higgs Boson Production and Decay Rates and Constraints on Its Couplings from a Combined ATLAS and CMS Analysis of the LHC Pp Collision Data at sqrt s written by and published by . This book was released on 2016 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combined ATLAS and CMS measurements of the Higgs boson production and decay rates, as well as constraints on its couplings to vector bosons and fermions, are presented. The combination is based on the analysis of five production processes, namely gluon fusion, vector boson fusion, and associated production with a W or a Z boson or a pair of top quarks, and of the six decay modes H → ZZ, W W , ??, ??, bb, and ??. All results are reported assuming a value of 125.09 GeV for the Higgs boson mass, the result of the combined measurement by the ATLAS and CMS experiments. The analysis uses the CERN LHC proton-proton collision data recorded by the ATLAS and CMS experiments in 2011 and 2012, corresponding to integrated luminosities per experiment of approximately 5 fb${̂–1}$ at $ sqrt{s}=7 $ TeV and 20 fb${̂–1}$ at $ sqrt{s}=8 $ TeV. The Higgs boson production and decay rates measured by the two experiments are combined within the context of three generic parameterisations: two based on cross sections and branching fractions, and one on ratios of coupling modifiers. Several interpretations of the measurements with more model-dependent parameterisations are also given. The combined signal yield relative to the Standard Model prediction is measured to be 1.09 ± 0.11. The combined measurements lead to observed significances for the vector boson fusion production process and for the H → ?? decay of 5.4 and 5.5 standard deviations, respectively. In conclusion, the data are consistent with the Standard Model predictions for all parameterisations considered.
