Measurement Of Top Quark Polarisation In T Channel Single Top Quark Production
DOWNLOAD
Download Measurement Of Top Quark Polarisation In T Channel Single Top Quark Production PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get Measurement Of Top Quark Polarisation In T Channel Single Top Quark Production book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
Measurement Of Top Quark Polarisation In T Channel Single Top Quark Production
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2015
Measurement Of Top Quark Polarisation In T Channel Single Top Quark Production written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2015 with categories.
Our first measurement of the top quark spin asymmetry, sensitive to the top quark polarisation, in t-channel single top quark production is presented. It is based on a sample of pp collisions at a centre-of-mass energy of 8 TeV corresponding to an integrated luminosity of 19.7 fb-1. A high-purity sample of t-channel single top quark events with an isolated muon is selected. Signal and background components are estimated using a fit to data. Furthermore, a differential cross section measurement, corrected for detector effects, of an angular observable sensitive to the top quark polarisation is performed. The differential distribution is used to extract a top quark spin asymmetry of 0.26 ± 0.03 (stat) ± 0.10 (syst), which is compatible with a p-value of 4.6% with the standard model prediction of 0.44.
Discovery Of Single Top Quark Production
DOWNLOAD
Author : Dag Gillberg
language : en
Publisher: Springer Science & Business Media
Release Date : 2011-01-22
Discovery Of Single Top Quark Production written by Dag Gillberg and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2011-01-22 with Science categories.
The top quark is by far the heaviest known fundamental particle with a mass nearing that of a gold atom. Because of this strikingly high mass, the top quark has several unique properties and might play an important role in electroweak symmetry breaking—the mechanism that gives all elementary particles mass. Creating top quarks requires access to very high energy collisions, and at present only the Tevatron collider at Fermilab is capable of reaching these energies. Until now, top quarks have only been observed produced in pairs via the strong interaction. At hadron colliders, it should also be possible to produce single top quarks via the electroweak interaction. Studies of single top quark production provide opportunities to measure the top quark spin, how top quarks mix with other quarks, and to look for new physics beyond the standard model. Because of these interesting properties, scientists have been looking for single top quarks for more than 15 years. This thesis presents the first discovery of single top quark production. It documents one of the flagship measurements of the D0 experiment, a collaboration of more than 600 physicists from around the world. It describes first observation of a physical process known as “single top quark production”, which had been sought for more than 10 years before its eventual discovery in 2009. Further, his thesis describes, in detail, the innovative approach Dr. Gillberg took to this analysis. Through the use of Boosted Decision Trees, a machine-learning technique, he observed the tiny single top signal within an otherwise overwhelming background. This Doctoral Thesis has been accepted by Simon Fraser University, Burnaby, BC, Canada.
Top Quark Physics At Hadron Colliders
DOWNLOAD
Author : Arnulf Quadt
language : en
Publisher: Springer Science & Business Media
Release Date : 2007-08-16
Top Quark Physics At Hadron Colliders written by Arnulf Quadt and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2007-08-16 with Science categories.
This will be a required acquisition text for academic libraries. More than ten years after its discovery, still relatively little is known about the top quark, the heaviest known elementary particle. This extensive survey summarizes and reviews top-quark physics based on the precision measurements at the Fermilab Tevatron Collider, as well as examining in detail the sensitivity of these experiments to new physics. Finally, the author provides an overview of top quark physics at the Large Hadron Collider.
Search For T Channel Single Top Quark Production In Pp Collisions At 1 96 Tev
DOWNLOAD
Author : Philip Michael Perea
language : en
Publisher:
Release Date : 2006
Search For T Channel Single Top Quark Production In Pp Collisions At 1 96 Tev written by Philip Michael Perea and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2006 with Collisions (Nuclear physics) categories.
Higgs Properties At The Lhc
DOWNLOAD
Author : Jason Tsz Shing Yue
language : en
Publisher: Springer
Release Date : 2017-08-29
Higgs Properties At The Lhc written by Jason Tsz Shing Yue and has been published by Springer this book supported file pdf, txt, epub, kindle and other format this book has been release on 2017-08-29 with Science categories.
This thesis studies the properties of the Higgs particle, discovered at the Large Hadron Collider (LHC) in 2012, in order to elucidate its role in electroweak symmetry breaking and cosmological phase transition in the early universe. It shows that a generic spin-2 Higgs impostor is excluded by the precision measurements of electroweak observables and perturbative unitarity considerations. It obtains LHC constraints on anomalous CP-violating Higgs-Top Yukawa couplings and examines the prospects of their measurement in future experiments. Lastly, it discusses in detail the electroweak phase transition and generation of cosmological matter–antimatter asymmetry in the universe with anomalous Higgs couplings.
Higher Order Qcd Corrections To Single Top Quark Production
DOWNLOAD
Author : Mohammad Assadsolimani
language : en
Publisher: disserta Verlag
Release Date : 2014-08
Higher Order Qcd Corrections To Single Top Quark Production written by Mohammad Assadsolimani and has been published by disserta Verlag this book supported file pdf, txt, epub, kindle and other format this book has been release on 2014-08 with Science categories.
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.
Physics At The Terascale
DOWNLOAD
Author : Ian Brock
language : en
Publisher: John Wiley & Sons
Release Date : 2011-05-04
Physics At The Terascale written by Ian Brock and has been published by John Wiley & Sons this book supported file pdf, txt, epub, kindle and other format this book has been release on 2011-05-04 with Science categories.
Written by authors working at the forefront of research, this accessible treatment presents the current status of the field of collider-based particle physics at the highest energies available, as well as recent results and experimental techniques. It is clearly divided into three sections; The first covers the physics -- discussing the various aspects of the Standard Model as well as its extensions, explaining important experimental results and highlighting the expectations from the Large Hadron Collider (LHC). The second is dedicated to the involved technologies and detector concepts, and the third covers the important - but often neglected - topics of the organisation and financing of high-energy physics research. A useful resource for students and researchers from high-energy physics.
The Large Hadron Collider
DOWNLOAD
Author : Thomas Schörner-Sadenius
language : en
Publisher: Springer
Release Date : 2015-05-15
The Large Hadron Collider written by Thomas Schörner-Sadenius and has been published by Springer this book supported file pdf, txt, epub, kindle and other format this book has been release on 2015-05-15 with Science categories.
This comprehensive volume summarizes and structures the multitude of results obtained at the LHC in its first running period and draws the grand picture of today’s physics at a hadron collider. Topics covered are Standard Model measurements, Higgs and top-quark physics, flavour physics, heavy-ion physics, and searches for supersymmetry and other extensions of the Standard Model. Emphasis is placed on overview and presentation of the lessons learned. Chapters on detectors and the LHC machine and a thorough outlook into the future complement the book. The individual chapters are written by teams of expert authors working at the forefront of LHC research.
Measurement Of The Polarisation Of Single Top Quarks And Antiquarks Produced In The T Channel At Square Root S
DOWNLOAD
Author : [Study Group] ATLAS Collaboration CERN
language : en
Publisher:
Release Date : 2022
Measurement Of The Polarisation Of Single Top Quarks And Antiquarks Produced In The T Channel At Square Root S written by [Study Group] ATLAS Collaboration CERN and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2022 with categories.
Abstract: A simultaneous measurement of the three components of the top-quark and top-antiquark polarisation vectors in t-channel single-top-quark production is presented. This analysis is based on data from proton-proton collisions at a centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 139 fb−1, collected with the ATLAS detector at the LHC. Selected events contain exactly one isolated electron or muon, large missing transverse momentum and exactly two jets, one being b-tagged. Stringent selection requirements are applied to discriminate t-channel single-top-quark events from the background contributions. The top-quark and top-antiquark polarisation vectors are measured from the distributions of the direction cosines of the charged-lepton momentum in the top-quark rest frame. The three components of the polarisation vector for the selected top-quark event sample are Px′ = 0.01 ± 0.18, Py′ = −0.029 ± 0.027, Pz′ = 0.91 ± 0.10 and for the top-antiquark event sample they are Px′ = −0.02 ± 0.20, Py′ = −0.007 ± 0.051, Pz′ = 0.79 ± 0.16. Normalised differential cross-sections corrected to a fiducial region at the stable-particle level are presented as a function of the charged-lepton angles for top-quark and top-antiquark events inclusively and separately. These measurements are in agreement with Standard Model predictions. The angular differential cross-sections are used to derive bounds on the complex Wilson coefficient of the dimension-six OtW operator in the framework of an effective field theory. The obtained bounds are CtW ∈ [−0.9, 1.4] and CitW ∈ [−0.8, 0.2], both at 95% confidence level
Search For Single Top Quark Production In Pp Collisions At Square Root Of Strange Quark
DOWNLOAD
Author : Sarah Kristina Wolinski
language : en
Publisher:
Release Date : 2002
Search For Single Top Quark Production In Pp Collisions At Square Root Of Strange Quark written by Sarah Kristina Wolinski and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2002 with categories.