Higher Order QCD Corrections to Single Top Quark Production

Higher Order QCD Corrections to Single Top Quark Production
Author: Mohammad Assadsolimani
Publisher: disserta Verlag
Total Pages: 161
Release: 2014-08
Genre: Science
ISBN: 3954256746

It is known that the LHC has a considerable discovery potential because of its large centre-of-mass energy (vs =14 TeV) and the high design luminosity. In addition, the two experiments ATLAS and CMS perform precision measurements for numerous models in physics. The increasing experimental precision demands an even higher level of accuracy on the theoretical side. For a more precise prediction of outcomes, one has to consider the corrections obtained typically from Quantum Chromodynamics (QCD). The calculation of these corrections in the high energy regime is described by perturbation theory. In the present study, multi-loop calculations in QCD, including in particular two-loop corrections for single top quark production, are considered. There are several phenomenological motivations to study single top quark production: Firstly, the process is sensitive to the electroweak Wtb-vertex; moreover, non-standard couplings can hint at physics beyond the Standard Model. Secondly, the t-channel cross section measurement provides information on the b-quark Parton Distribution Functions (PDF). Finally, single top quark production enables us to directly measure the Cabibbo-Kobayashi-Maskawa(CKM) matrix element Vtb. The next-to-next-to-leading-order (NNLO) calculation of the single top quark production has many building blocks. In this study, two blocks will be presented: one-loop corrections squared and two-loop corrections interfered with Born. Initially, the one-loop squared contribution at NNLO for single top quark production will be calculated. Before we begin with the calculation of the two-loop corrections to single top quark production, we calculate the QCD form factors of heavy quarks at NNLO, along with the axial vector coupling as a first independent check. A comparison with the relevant literature suggests that this approach is in line with generally accepted procedure. This consistency check provides a proof of the validity of our setup. In the next step, the two-loop corrections to single top quark production will be calculated. After reducing all occurring tensor integrals to scalar integrals, we apply the integration by parts method (IBP) to find the master integrals. This step is a major challenge compared to all similar calculations because of the number of variables in the problem (two Mandelstam variables s and t, the dimension d and the mass of the top quark mt as well as the mass of the W boson mw). Finally, the calculation of the three kinds of topologies – vertex corrections, double boxes and non-planar double boxes – in the two-loop contribution at NNLO calculation will be presented.

Techniques and Concepts of High-Energy Physics IX

Techniques and Concepts of High-Energy Physics IX
Author: Thomas Ferbel
Publisher: Springer Science & Business Media
Total Pages: 541
Release: 2012-12-06
Genre: Science
ISBN: 1461559634

The ninth Advanced Study Institute (AS!) on Techniques and Concepts of High Energy Physics was almost canceled before ifbegan! A certain visitor to the area (Hurricane Bertha) arrived unexpectedly early in 1996. It was the first hur ricane in memory to menace the Caribbean in early July! Fortunately, it passed St. Croix several days before our meeting, and left very little damage. (The Altar ellis survived the eye of the storm in the in the British West Islands!) The meeting was held once again at the hotel on the Cay, on that spec of land in the harbor ofChrirtiansted, St. Croix, U. S. Virgin Islands. After the first two days of, at times, outrageous downpour, the 71 participants from 26 coun tries began to relax and enjoy the lectures and the lovely surroundings of the In stitute. The primary support for the meeting was provided by the ~cientific Affairs Division of the North Atlantic Treaty Organization (NATO). The ASI was cosponsored by the U. S. department of Energy, by the Fermi National Accelera tor Laboratory (Fermi-lab), by the U. S. National Science Foundation, and by the University of Rochester. In addition, the International Science Foundation con tributed to the support of a participant from Russia. As in the case of the previous ASIs, the scientific program was designed for advanced graduate students and recent Ph. D. recipients in experimental parti cle physics.

Theory Meets Experiment - Proceedings Of The Johns Hopkins Workshop On Current Problems In Particle Theory 18

Theory Meets Experiment - Proceedings Of The Johns Hopkins Workshop On Current Problems In Particle Theory 18
Author: Roberto Casalbuoni
Publisher: World Scientific
Total Pages: 318
Release: 1995-06-29
Genre:
ISBN: 9814549363

The workshop collected together theoreticians and experimentalists for a discussion about the most recent experiments and their impact on theoretical ideas. The discussion included the new data from LEP and SLD, the evidence for the top quark from Tevatron, the structure function measurements from HERA, and the searches for dark matter. Also, new projects for physics with large neutrino detectors and CP violation at e+e- factories were presented, and a survey of high energy astroparticle physics was included. Particular attention was paid to the interplay between microscopical and cosmological scales.

Particle Physics: Perspectives And Opportunities - Report Of The Dpf Committee On Long-term Planning

Particle Physics: Perspectives And Opportunities - Report Of The Dpf Committee On Long-term Planning
Author: Robert N Cahn
Publisher: World Scientific
Total Pages: 318
Release: 1995-09-20
Genre:
ISBN: 9814549223

This book is the result of a broad-based and in-depth study of high energy physics commissioned by the Executive Committee of the Division of Particles and Fields of the American Physical Society. This year-long study was initiated in the early 1994, in the wake of the cancellation of the SSC, and is meant to complement the report of the Drell HEPAP subpanel, charged with providing a vision for the future of the field. The DPF study of high energy physics was organized on the basis of the working groups, each led by a number of co-conveners chosen among established leaders in the various subspecialties in the field. These conveners, in turn, organized their working groups by inviting other active workers in the discipline to participate and gathered further input from the community by holding a variety of specialized meetings and workshops. This book contains the final reports of the 11 working groups assembled for the study, along with an extended overview and executive summary by the editors.

QCD Higher-Order Effects and Search for New Physics

QCD Higher-Order Effects and Search for New Physics
Author: Jian Wang
Publisher: Springer
Total Pages: 153
Release: 2015-10-28
Genre: Science
ISBN: 3662486733

This book mainly investigates the precision predictions on the signal of new physics at the Large Hadron Collider (LHC) in the perturbative Quantum Chromodynamics (QCD) scheme. The potential of the LHC to discover the signal of dark matter associated production with a photon is studied after including next-to-leading order QCD corrections. The factorization and resummation of t-channel top quark transverse momentum distribution in the standard model at both the Tevatron and the LHC with soft-collinear effective theory are presented. The potential of the early LHC to discover the signal of monotops is discussed. These examples illustrate the method of searching for new physics beyond what is known today with high precision.

New Computing Techniques In Physics Research Iii - Proceedings Of The 3rd International Workshop On Software Engineering, Ai And Expert Systems For High Energy And Nuclear Physics

New Computing Techniques In Physics Research Iii - Proceedings Of The 3rd International Workshop On Software Engineering, Ai And Expert Systems For High Energy And Nuclear Physics
Author: K H Becks
Publisher: World Scientific
Total Pages: 684
Release: 1994-02-04
Genre:
ISBN: 9814551708

No basic or applied physics research can be done nowadays without the support of computing systems, ranging from cheap personal computers to large multi-user mainframes. Some research fields like high energy physics would not exist if computers had not been invented. Departing from the more conventional numerical applications, this series of workshops has been initiated to focus on Artificial Intelligence (AI) related developments, such as symbolic manipulation for lengthy and involved algebraic computations, software engineering to assist groups of developers in the design, coding and maintenance of large packages, expert systems to mimic human reasoning and strategy in the diagnosis of equipment or neural networks to implement a model of the brain to solve pattern recognition problems. These techniques, developed some time ago by AI researchers, are confronted by down-to-earth problems arising in high-energy and nuclear physics. All this and more are covered in these proceedings.

Frontiers in Particle Physics

Frontiers in Particle Physics
Author: Jean-Marc Gérard
Publisher: Springer Science & Business Media
Total Pages: 461
Release: 2013-12-01
Genre: Science
ISBN: 1489910824

Proceedings of a NATO ASI held in Cargese, France, August 1-13, 1994

The Higgs Hunter's Guide

The Higgs Hunter's Guide
Author: John F. Gunion
Publisher: CRC Press
Total Pages: 333
Release: 2018-03-05
Genre: Science
ISBN: 0429976070

The Higgs Hunter's Guide is a definitive and comprehensive guide to the physics of Higgs bosons. In particular, it discusses the extended Higgs sectors required by those recent theoretical approaches that go beyond the Standard Model, including supersymmetry and superstring-inspired models.

Hadrons and Hadronic Matter

Hadrons and Hadronic Matter
Author: Dominique Vautherin
Publisher: Springer Science & Business Media
Total Pages: 419
Release: 2012-12-06
Genre: Science
ISBN: 1468413368

Proceedings of a NATO ASI held in Cargese, France, August 8-18, 1989