Download or read book Impact of SUSY QCD Corrections on Top Quark Decay Distributions written by Arnd Brandenburg and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings of the International Conference on QCD and Hadronic Physics Peking University China 16 20 June 2005 written by and published by . This book was released on 2006 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book B Decays written by Sheldon Stone and published by World Scientific. This book was released on 1992-03-27 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of b quarks has now reached a stage where it is useful to review what has been learned so far and also to look at the implications of future studies. The most important observations thus far — measurement of the “B” lifetime, B0 — B0 mixing, and the observation of b→ u transitions, as well as more mundane results on hadronic and semileptonic transitions — are described in detail by experimentalists who have been closely involved with the measurements. Theoretical progress in understanding b quark decays, including the mechanisms of hadronic and semileptonic decays, are described. Synthesizing the experimental and theoretical information, the authors discuss tests of the standard model and measurements of standard model parameters. Possibilities of more extensive tests using measurement of CP violation in the B system are also addressed.

Download or read book Higher Order QCD Corrections to Single Top Quark Production written by Mohammad Assadsolimani and published by disserta Verlag. This book was released on 2014-08 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book SUSY QCD Corrections to the Polarization and Spin Correlations of Top Quarks Produced in E e Collisions written by A. Brandenburg and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiative Corrections to the Decay of the Top Quark written by Luisa Oggero and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Zusammenfassung: The calculation of the NLO electroweak and QCD corrections to the top-quark decay width, including the W-boson decay and off-shell effects is presented. Both the semileptonic and the hadronic decays are considered. The one-cutoff slicing method has been extended to decay processes with more than two charged particles, to deal with soft and collinear divergences. Its generalization has been obtained using mass regularization. In order to check the validity of the method employed, the calculation has been compared against an independent one and against the values obtained using the narrow-width approximation. Furthermore, the total top-quark decay width has been calculated and compared with the existing experimental measurements.

Download or read book QCD Radiation in Top Antitop and Z Jets Final States written by Kiran Joshi and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis contains new research in both experimental and theoretical particle physics, making important contributions in each. Two analyses of collision data from the ATLAS experiment at the LHC are presented, as well as two phenomenological studies of heavy coloured resonances that could be produced at the LHC. The first data analysis was the measurement of top quark-antiquark production with a veto on additional jet activity. As the first detector-corrected measurement of jet activity in top-antitop events it played an important role in constraining the theoretical modelling, and ultimately reduced these uncertainties for ATLAS's other top-quark measurements by a factor of two. The second data analysis was the measurement of Z+2jet production and the observation of the electroweak vector boson fusion (VBF) component. As the first observation of VBF at a hadron collider, this measurement demonstrated new techniques to reliably extract VBF processes and paved the way for future VBF Higgs measurements. The first phenomenological study developed a new technique for identifying the colour of heavy resonances produced in proton-proton collisions. As a by-product of this study an unexpected and previously unnoticed correlation was discovered between the probability of correctly identifying a high-energy top and the colour structure of the event it was produced in. The second phenomenological study explored this relationship in more detail, and could have important consequences for the identification of new particles that decay to top quarks.

Download or read book SUSY QCD Corrections to the Polarization and Spin Correlations of Top Quarks Produced in E e Collisions written by Arnd Brandenburg and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Science Reports of the T hoku University written by and published by . This book was released on 2000 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes Annual reports for the Physics and Astronomy Departments.

Download or read book THE TOP QUARK QCD AND NEW PHYSICS written by and published by . This book was released on 2002 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: The role of the top quark in completing the Standard Model quark sector is reviewed, along with a discussion of production, decay, and theoretical restrictions on the top quark properties. Particular attention is paid to the top quark as a laboratory for perturbative QCD. As examples of the relevance of QCD corrections in the top quark sector, the calculation of ee− + t{bar t} at next-to-leading-order QCD using the phase space slicing algorithm and the implications of a precision measurement of the top quark mass are discussed in detail. The associated production of a t{bar t} pair and a Higgs boson in either ee− or hadronic collisions is presented at next-to-leading-order QCD and its importance for a measurement of the top quark Yulrawa coupling emphasized. Implications of the heavy top quark mass for model builders are briefly examined, with the minimal supersymmetric Standard Model and topcolor discussed as specific examples.

Download or read book Supersymmetry and the Unification of Fundamental Interactions written by Deog Ki Hong and published by AIP Conference Proceedings (Nu. This book was released on 2008-12-11 with total page 670 pages. Available in PDF, EPUB and Kindle. Book excerpt: This annual SUSY conference has become the world's largest international meeting devolted to new ideas in high energy physics. The main subject of the conference is theoretical and phenomenological aspects of supersymmetric theories, and dark matter and dark energy, and other comological connections. New, interesting results from various experimental groups are increasingly presented at the conference as well. With roughly 200 plenary and parallel presentations, SUSY08 will likely deliver energy and enthusiasm of both theorists and experimentalists who are searching the frontier of high energy physics.

Download or read book Impact of SUSY QCD Corrections on Neutralino stop Co annihilation and the Neutralino Relic Density written by and published by . This book was released on 2013 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book QCD Higher Order Effects and Search for New Physics written by Jian Wang and published by Springer. This book was released on 2015-10-28 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book E e Collisions at 500 GeV written by Peter Zerwas and published by . This book was released on 1992 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Physics and Experimentation at a Linear Electron positron Collider written by and published by . This book was released on 2001 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Physics at the Large Hadron Collider written by Amitava Datta and published by Springer Science & Business Media. This book was released on 2010-05-30 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: In an epoch when particle physics is awaiting a major step forward, the Large Hydron Collider (LHC) at CERN, Geneva will soon be operational. It will collide a beam of high energy protons with another similar beam circulation in the same 27 km tunnel but in the opposite direction, resulting in the production of many elementary particles some never created in the laboratory before. It is widely expected that the LHC will discover the Higgs boson, the particle which supposedly lends masses to all other fundamental particles. In addition, the question as to whether there is some new law of physics at such high energy is likely to be answered through this experiment. The present volume contains a collection of articles written by international experts, both theoreticians and experimentalists, from India and abroad, which aims to acquaint a non-specialist with some basic issues related to the LHC. At the same time, it is expected to be a useful, rudimentary companion of introductory exposition and technical expertise alike, and it is hoped to become unique in its kind. The fact that there is substantial Indian involvement in the entire LHC endeavour, at all levels including fabrication, physics analysis procedures as well as theoretical studies, is also amply brought out in the collection.

Download or read book QCD Corrections to Higgs Boson Production written by and published by . This book was released on 1992 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We discuss the O([alpha][sub s]) QCD radiative corrections to Higgs boson production in the limit in which the top quark is much heavier than the Higgs boson. The subleading corrections, of O([alpha][sub s]M[sub H][sup 2]/M[sub top][sup 2]), are presented for the decay H [yields] [gamma][gamma] and shown to be small.