Measurement of Higgs Boson Production Cross Sections in the Diphoton Channel

Measurement of Higgs Boson Production Cross Sections in the Diphoton Channel PDF

Author: Ahmed Tarek Abouelfadl Mohamed

Publisher: Springer Nature

Published: 2020-11-12

Total Pages: 305

ISBN-13: 3030595161

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This thesis presents the measurement of the Higgs boson cross section in the diphoton decay channel. The measurement relies on proton-proton collision data at a center-of-mass energy √s = 13 TeV recorded by the ATLAS experiment at the Large Hadron Collider (LHC). The collected data correspond to the full Run-2 dataset with an integrated luminosity of 139 fb-1. The measured cross sections are used to constrain anomalous Higgs boson interactions in the Effective Field Theory (EFT) framework. The results presented in this thesis represent a reduction by a factor 2 of the different photon and jet energy scale and resolution systematic uncertainties with respect to the previous ATLAS publication. The thesis details the calibration of electron and photon energies in ATLAS, in particular the measurement of the presampler energy scale and the estimation of its systematic uncertainty. This calibration was used to perform a measurement of the Higgs boson mass in the H → γγ and H → 4l channels using the 36 fb−1 dataset.

Measurement of Differential Cross Sections for Higgs Boson Production in the Diphoton Decay Channel in Pp Collisions at $\sqrt{s}$

Measurement of Differential Cross Sections for Higgs Boson Production in the Diphoton Decay Channel in Pp Collisions at $\sqrt{s}$ PDF

Author:

Publisher:

Published: 2016

Total Pages: 31

ISBN-13:

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Here, we presented a measurement of differential cross sections for the Higgs boson (H) production in pp collisions at √s = 8 TeV. The analysis exploits the H →?? decay in data corresponding to an integrated luminosity of 19.7 fb-1 collected by the CMS experiment at the LHC. The cross section is measured as a function of the kinematic properties of the diphoton system and of the associated jets. Results corrected for detector effects are compared with predictions at next-to-leading order and nextto-next-to-leading order in perturbative quantum chromodynamics, as well as with predictions beyond the standard model. Furthermore, for isolated photons with pseudorapidities.

Higgs Boson Cross Section Measurements in the Diphoton Decay Channel in Proton-proton Collisions at √s

Higgs Boson Cross Section Measurements in the Diphoton Decay Channel in Proton-proton Collisions at √s PDF

Author: Ivan Konstantinovich Pogrebnyak

Publisher:

Published: 2021

Total Pages: 322

ISBN-13:

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This dissertation presents ATLAS measurements of the total and differential fiducial cross sections for the process of the Higgs boson production and subsequent decay to two photons. The analyzed dataset of proton-proton collisions at √s = 13 TeV has an integrated luminosity of 139 ifb and was collected during the Run 2 of the Large Hadron Collider in 2015–2018. The cross sections were measured in a fiducial phase space closely matching the experimental selection, and compared to the Standard Model predictions from the state-of-the-art calculations. The differential cross sections were measured with respect to an array of observables, allowing us to probe the kinematics, jet activity, and spin and CP properties of the Higgs boson interactions. The data were analyzed iteratively, with yearly results from partial datasets presented at conferences and in publications. The inclusive fiducial cross section obtained from the analysis of the full Run 2 dataset is 65.2 ± 4.5 (stat.) ± 5.6 (exp.) ± 0.3 (theory) fb, which is in excellent agreement with the SM prediction of 63.5 ± 3.3 fb. The results provide the state-of-the-art experimental measurements of the Higgs boson production cross sections, and extend our confidence in the SM in the Higgs sector and QCD, as well as in the computational techniques used to obtain theoretical predictions.

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

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

Author: [Study Group] ATLAS Collaboration CERN

Publisher:

Published: 2022

Total Pages: 0

ISBN-13:

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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

Discovery of the Higgs Boson with the Diphoton Decay Channel and First Differential Cross-section Measurements with ATLAS

Discovery of the Higgs Boson with the Diphoton Decay Channel and First Differential Cross-section Measurements with ATLAS PDF

Author:

Publisher:

Published: 2015

Total Pages: 0

ISBN-13:

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In July 2012, a Higgs boson was discovered by both the ATLAS and CMS experiments. This thesis presents the most recent version of the H ->[gamma][gamma] analysis that was used in the discovery. Since the discovery, focus has shifted to measure the properties of the Higgs boson. The analysis presented here is the analysis of the Higgs couplings, where events are divided into twelve categories defined to isolate the various production processes. Specific focus is given to the vector boson fusion (VBF) process where the Higgs boson is produced in association with two foward/backward jets. Due to its small theory errors, the VBF process can allow for very precise measurements of the Higgs boson's properties. Also presented are the first differential cross section measurements for the Higgs boson as measured in the diphoton decay channel. Distributions in data are unfolded to particle level and compared with the latest Monte Carlo event generators for gluon-gluon fusion. Many distributions concentrate on the kinematics of the Higgs boson produced in association with jets. Finally, a proposal for a 1-jet VBF region for the high-luminosity LHC is proposed based on the difference in rapidity between the Higgs boson and the leading jet. This region shows good discrimination power against gluon-gluon fusion events and has been shown to discriminate against beyond the Standard Model couplings.

Measurement of Differential and Integrated Fiducial Cross Sections for Higgs Boson Production in the Four-lepton Decay Channel in Pp Collisions at $ \sqrt{s}

Measurement of Differential and Integrated Fiducial Cross Sections for Higgs Boson Production in the Four-lepton Decay Channel in Pp Collisions at $ \sqrt{s} PDF

Author:

Publisher:

Published: 2016

Total Pages: 46

ISBN-13:

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Integrated fiducial cross sections for the production of four leptons via the H → 4l decays (l = e, [mu]) are measured in pp collisions at $ \sqrt{s}=7 $ and 8TeV. Measurements are performed with data corresponding to integrated luminosities of 5.1 fb$^{-1}$ at 7TeV, and 19.7 fb$^{-1}$ at 8 TeV, collected with the CMS experiment at the LHC. Differential cross sections are measured using the 8 TeV data, and are determined as functions of the transverse momentum and rapidity of the four-lepton system, accompanying jet multiplicity, transverse momentum of the leading jet, and difference in rapidity between the Higgs boson candidate and the leading jet. A measurement of the Z → 4l cross section, and its ratio to the H → 4l cross section is also performed. All cross sections are measured within a fiducial phase space defined by the requirements on lepton kinematics and event topology. Here, the integrated H → 4l fiducial cross section is measured to be 0.56$_{-0.44}^{+0.67}$ (stat)$_{-0.06}^{+0.21}$ (syst) fb at 7 TeV, and 1.11$_{-0.35}^{+0.41}$ (stat)$_{-0.10}^{+0.14}$ (syst) fb at 8 TeV. The measurements are found to be compatible with theoretical calculations based on the standard model.

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]"

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]

Author:

Publisher:

Published: 2015

Total Pages:

ISBN-13:

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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.

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