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
ISBN: 3030595161
Category : Science
Languages : en
Pages : 318

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Book Description
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 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
ISBN: 3030595161
Category : Science
Languages : en
Pages : 318

Get Book Here

Book Description
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.

ATLAS Measurements of the Higgs Boson Coupling to the Top Quark in the Higgs to Diphoton Decay Channel

ATLAS Measurements of the Higgs Boson Coupling to the Top Quark in the Higgs to Diphoton Decay Channel PDF Author: Jennet Elizabeth Dickinson
Publisher: Springer Nature
ISBN: 3030863689
Category : Science
Languages : en
Pages : 233

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Book Description
During Run 2 of the Large Hadron Collider, the ATLAS experiment recorded proton-proton collision events at 13 TeV, the highest energy ever achieved in a collider. Analysis of this dataset has provided new opportunities for precision measurements of the Higgs boson, including its interaction with the top quark. The Higgs-top coupling can be directly probed through the production of a Higgs boson in association with a top-antitop quark pair (ttH). The Higgs to diphoton decay channel is among the most sensitive for ttH measurements due to the excellent diphoton mass resolution of the ATLAS detector and the clean signature of this decay. Event selection criteria were developed using novel Machine Learning techniques to target ttH events, yielding a precise measurement of the ttH cross section in the diphoton channel and a 6.3 $\sigma$ observation of the ttH process in combination with other decay channels, as well as stringent limits on CP violation in the Higgs-top coupling.

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:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
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

Particle Physics Reference Library

Particle Physics Reference Library PDF Author: Herwig Schopper
Publisher: Springer Nature
ISBN: 3030382079
Category : Heavy ions
Languages : en
Pages : 632

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Book Description
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

Foundations of Perturbative QCD

Foundations of Perturbative QCD PDF Author: John Collins
Publisher: Cambridge University Press
ISBN: 1139500627
Category : Science
Languages : en
Pages : 637

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Book Description
Giving an accurate account of the concepts, theorems and their justification, this book is a systematic treatment of perturbative QCD. It relates the concepts to experimental data, giving strong motivations for the methods. Ideal for graduate students starting their work in high-energy physics, it will also interest experienced researchers.

Higgs, Supersymmetry and Dark Matter After Run I of the LHC

Higgs, Supersymmetry and Dark Matter After Run I of the LHC PDF Author: Béranger Dumont
Publisher: Springer
ISBN: 3319449567
Category : Science
Languages : en
Pages : 271

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Book Description
This work was nominated as an outstanding PhD thesis by the LPSC, Université Grenoble Alpes, France. The LHC Run 1 was a milestone in particle physics, leading to the discovery of the Higgs boson, the last missing piece of the so-called "Standard Model" (SM), and to important constraints on new physics, which challenge popular theories like weak-scale supersymmetry. This thesis provides a detailed account of the legacy of the LHC Run 1 ≤¥regarding these aspects. First, the SM and the need for its extension are presented in a concise yet revealing way. Subsequently, the impact of the LHC Higgs results on scenarios of new physics is assessed in detail, including a careful discussion of the relevant uncertainties. Two approaches are considered: generic modifications of the Higgs couplings, possibly arising from extended Higgs sectors or higher-dimensional operators; and tests of specific new physics models. Lastly, the implications of the null results of the searches for new physics are discussed with a particular focus on supersymmetric dark matter candidates. Here as well, two approaches are presented: the "simplified models" approach, and recasting by event simulation. This thesis stands out for its educational approach, its clear language and the depth of the physics discussion. The methods and tools presented offer readers essential practical tools for future research.

Fundamental Interactions

Fundamental Interactions PDF Author: A. Astbury
Publisher: World Scientific
ISBN: 9814280941
Category : Science
Languages : en
Pages : 429

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Book Description
This book contains pedagogical lectures on both theoretical and experimental particle physics, cosmology, and atomic trap physics. Numerous additional contributions provide up-to-date information on new experimental results from accelerators, underground laboratories, and nuclear astrophysics. This combination of pedagogical talks and topical short discussions presents a comprehensive amount of information and latest developments to researchers. Sample Chapter(s). Chapter 1: New Physics and the LHC (9,214 KB). Contents: New Physics and the LHC (G Altarelli); Very High Energy Cosmic Rays: Results from the Pierre Auger Observatory (C E Covault); Neutrinos at Lake Louise (S Davidson); Physics Impact of the Tevatron (D C O''Neil); Cosmology and the LHC (V Rubakov); CMK Angle Measurements from BABAR (J M Anderson); An Overview of Top Quark Analyses from the CMS Collaboration (J Andrea); Heavy Quark Production at HERA and Heavy Quark Contributions to the Proton Structure Function (D Bartsch); ATLAS Commissioning and Physics with Early Data (P J Bell); Search for Heavy Stable Charged Particles at CMS (J Chen); A High-Sensitivity Search for Charged Lepton Flavor Violation at Fermilab (E C Dukes); Prospects for CP Violation Studies at LHCb (V V Gligorov); Measurements of a 3 () at Belle (Y Horii); High P T Jets and Photons at Dy (Z Hubacek); SUSY Search at ATLAS (Y Kataoka); Neutrino Physics with the IceCube Detector (J Kirkyluk); Determination of the Strong Phase in D 0 OaAE K + C - Using Quantum-Correlated Measurements (A Lincoln); Results on Top Quark Physics at Dy (Y Peters); Quarkonium Production and Polarisation with Early Data at ATLAS (D D Price); and other papers. Readership: Graduate students, researchers and academics in high energy physics (HEP), astrophysics and atomic physics."

Fundamental Interactions - Proceedings Of The 23rd Lake Louise Winter Institute 2008

Fundamental Interactions - Proceedings Of The 23rd Lake Louise Winter Institute 2008 PDF Author: Alan Astbury
Publisher: World Scientific
ISBN: 981446709X
Category : Science
Languages : en
Pages : 429

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Book Description
This book contains pedagogical lectures on both theoretical and experimental particle physics, cosmology, and atomic trap physics. Numerous additional contributions provide up-to-date information on new experimental results from accelerators, underground laboratories, and nuclear astrophysics. This combination of pedagogical talks and topical short discussions presents a comprehensive amount of information and latest developments to researchers.

Future Of The Large Hadron Collider, The: A Super-accelerator With Multiple Possible Lives

Future Of The Large Hadron Collider, The: A Super-accelerator With Multiple Possible Lives PDF Author: Oliver Bruning
Publisher: World Scientific
ISBN: 9811280193
Category : Science
Languages : en
Pages : 455

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Book Description
The Large Hadron Collider (LHC) is the highest energy collider ever built. It resides near Geneva in a tunnel 3.8m wide, with a circumference of 26.7km, which was excavated in 1983-1988 to initially house the electron-positron collider LEP. The LHC was approved in 1995, and it took until 2010 for reliable operation. By now, a larger set of larger integrated luminosities have been accumulated for physics analyses in the four collider experiments: ATLAS, CMS, LHCb and ALICE.The LHC operates with an extended cryogenic plant, using a multi-stage injection system comprising the PS and SPS accelerators (still in use for particle physics experiments at lower energies). The beams are guided by 1232 superconducting high field dipole magnets.Intense works are underway in preparation of the High Luminosity LHC, aimed at upgrading the LHC and detectors for collecting ten times more luminosity, and extending the collider life to the early 2040's. So far, the (HL-)LHC project represents a cumulation of around one hundred thousand person-years of innovative work by technicians, engineers, and physicists from all over the world; probably the largest scientific effort ever in the history of humanity. The book is driven by the realisation of the unique value of this accelerator complex and by the recognition of the status of high energy physics, described by a Standard Model — which still leaves too many questions unanswered to be the appropriate theory of elementary particles and their interactions.Following the Introduction are: three chapters which focus on the initial decade of operation, leading to the celebrated discovery of the Higgs Boson, on the techniques and physics of the luminosity upgrade, and finally on major options - of using the LHC in a concurrent, power economic, electron-hadron scattering mode, when upgraded to higher energies or eventually as an injector for the next big machine. The various technical and physics chapters, provided by 61 authors, characterise the fascinating opportunities the LHC offers for the next two decades ahead (possibly longer), with the goal to substantially advance our understanding of nature.

Lepton Photon Interactions At High Energies (Lepton Photon 2017) - Proceedings Of The 28th International Symposium

Lepton Photon Interactions At High Energies (Lepton Photon 2017) - Proceedings Of The 28th International Symposium PDF Author: Wei Wang
Publisher: World Scientific
ISBN: 9811207410
Category : Science
Languages : en
Pages : 576

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Book Description
The latest of the 'Lepton Photon' symposium, one of the well-established series of meetings in the high-energy physics community, was successfully organized at the South Campus of Sun Yat-sen University, Guangzhou, China, from August 7-12, 2017, where physicists around the world gathered to discuss the latest advancements in the research field.This proceedings volume of the Lepton Photon 2017 collects contributions by the plenary session speakers and the posters' presenters, which cover the latest results in particle physics, nuclear physics, astrophysics, cosmology, and plans for future facilities.