Download or read book Top Quark Pair Production Cross Sections and Calibration of the Top Quark Monte Carlo Mass written by Jan Kieseler and published by Springer. This book was released on 2016-06-15 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the first experimental calibration of the top-quark Monte-Carlo mass. It also provides the top-quark mass-independent and most precise top-quark pair production cross-section measurement to date. The most precise measurements of the top-quark mass obtain the top-quark mass parameter (Monte-Carlo mass) used in simulations, which are partially based on heuristic models. Its interpretation in terms of mass parameters used in theoretical calculations, e.g. a running or a pole mass, has been a long-standing open problem with far-reaching implications beyond particle physics, even affecting conclusions on the stability of the vacuum state of our universe. In this thesis, this problem is solved experimentally in three steps using data obtained with the compact muon solenoid (CMS) detector. The most precise top-quark pair production cross-section measurements to date are performed. The Monte-Carlo mass is determined and a new method for extracting the top-quark mass from theoretical calculations is presented. Lastly, the top-quark production cross-sections are obtained – for the first time – without residual dependence on the top-quark mass, are interpreted using theoretical calculations to determine the top-quark running- and pole mass with unprecedented precision, and are fully consistently compared with the simultaneously obtained top-quark Monte-Carlo mass.
Download or read book Measurement of the Top Quark Mass in the Dilepton Final State Using the Matrix Element Method written by Alexander Grohsjean and published by Springer Science & Business Media. This book was released on 2010-10-01 with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main pacemakers of scienti?c research are curiosity, ingenuity, and a pinch of persistence. Equipped with these characteristics a young researcher will be s- cessful in pushing scienti?c discoveries. And there is still a lot to discover and to understand. In the course of understanding the origin and structure of matter it is now known that all matter is made up of six types of quarks. Each of these carry a different mass. But neither are the particular mass values understood nor is it known why elementary particles carry mass at all. One could perhaps accept some small generic mass value for every quark, but nature has decided differently. Two quarks are extremely light, three more have a somewhat typical mass value, but one quark is extremely massive. It is the top quark, the heaviest quark and even the heaviest elementary particle that we know, carrying a mass as large as the mass of three iron nuclei. Even though there exists no explanation of why different particle types carry certain masses, the internal consistency of the currently best theory—the standard model of particle physics—yields a relation between the masses of the top quark, the so-called W boson, and the yet unobserved Higgs particle. Therefore, when one assumes validity of the model, it is even possible to take precise measurements of the top quark mass to predict the mass of the Higgs (and potentially other yet unobserved) particles.
Download or read book CMS Pixel Detector Upgrade and Top Quark Pole Mass Determination written by Simon Spannagel and published by Springer. This book was released on 2017-08-01 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis addresses two different topics, both vital for implementing modern high-energy physics experiments: detector development and data analysis. Providing a concise introduction to both the standard model of particle physics and the basic principles of semiconductor tracking detectors, it presents the first measurement of the top quark pole mass from the differential cross-section of tt+J events in the dileptonic tt decay channel. The first part focuses on the development and characterization of silicon pixel detectors. To account for the expected increase in luminosity of the Large Hadron Collider (LHC), the pixel detector of the compact muon solenoid (CMS) experiment is replaced by an upgraded detector with new front-end electronics. It presents comprehensive test beam studies conducted to verify the design and quantify the performance of the new front-end in terms of tracking efficiency and spatial resolution. Furthermore, it proposes a new cluster interpolation method, which utilizes the third central moment of the cluster charge distribution to improve the position resolution. The second part of the thesis introduces an alternative measurement of the top quark mass from the normalized differential production cross-sections of dileptonic top quark pair events with an additional jet. The energy measurement is 8TeV. Using theoretical predictions at next-to-leading order in perturbative Quantum Chromodynamics (QCD), the top quark pole mass is determined using a template fit method.
Download or read book Symmetry in Particle Physics written by Michal Hnatič and published by MDPI. This book was released on 2021-06-24 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Particle physics is a science about the symmetries of our world. The Standard Model is the fundamental theory of microworld. Particle dynamics in the Standard Model obeys strict symmetry laws with explicit experimental consequences. Priority problems of particle physics based on the Standard Model are more accurate theoretical predictions, experimental measurements and data analysis, proof of existence or non-existence of supersymmetry, top quark properties, Higgs boson, exotic quark states, and physics of neutrinos. In this collection of articles, many of these problems are discussed. We recommend this book for students, graduate students, and scientists working in the field of high energy physics.
Download or read book Eps High Energy Physics 95 Proceedings Of The International Europhysics Conference written by Catherine Vander Velde and published by World Scientific. This book was released on 1996-05-28 with total page 1042 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Evidence for the Top Quark written by Kent W. Staley and published by Cambridge University Press. This book was released on 2004-04-05 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Evidence for the Top Quark offers both a historical and philosophical perspective on an important recent discovery in particle physics: the first evidence for the elementary particle known as the top quark. Drawing on published reports, oral histories, and internal documents from the large collaboration that performed the experiment, Kent Staley explores in detail the controversies and politics that surrounded this major scientific result.At the same time the book seeks to defend an objective theory of scientific evidence based on error probabilities.
Download or read book Spin Correlations in tt Events from pp Collisions written by Boris Lemmer and published by Springer. This book was released on 2015-06-24 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis introduces readers to the Standard Model, the top quark and its properties, before explaining the concept of spin correlation measurement. The first measurement of top quark spin correlations at the LHC in the lepton+jets decay channel is presented. As the heaviest elementary particle, the top quark plays an essential role in the Standard Model of elementary particle physics. In the case of top quarks being produced in pairs at hadron colliders, the Standard Model predicts their spins to be correlated. The degree of correlation depends on both the production mechanism and properties of the top quark. Any deviation from the Standard Model prediction can be an indicator for new physics phenomena. The thesis employs an advanced top quark reconstruction algorithm including dedicated identification of the up- and down-type quarks from the W boson decay.
Download or read book Astroparticle Particle Space Physics and Detectors for Physics Applications written by S. Giani and published by World Scientific. This book was released on 2012 with total page 1100 pages. Available in PDF, EPUB and Kindle. Book excerpt: The exploration of the subnuclear world is done through increasingly complex experiments covering a wide range of energy and performed in a large variety of environments ranging from particle accelerators, underground detectors to satellites and the space laboratory. Among recent advances one has to indicate, for instance, first results obtained from space and LHC experiments and progress done in preparation of the latter experiments upgrades, including plans for the LHC machine upgrade. The achievement of these research programs calls for novel techniques, new materials and instrumentation to be used in detectors, often of large scale. Therefore, fundamental physics is at the forefront of technological advance and also leads to many applications. Among these, medical applications have a particular importance due to health and social benefits they bring to the public. Sample Chapter(s). Science highlights from the Fenni Observatory (5,046 KB). Contents: Space Experiments and Cosmic Rays Observations; Production and Propagation of Cosmic Rays in the Galaxy and Heliosphere; Dark Matter Searches, Underwater and Underground Experiments; High Energy Physics Experiments; Tracker and Position Sensitive Detectors; Calorimetry; Advanced Detectors, Particles Identication, Devices and Materials in Radiation; Broader Impact Activities, Treatments and Software Application. Readership: Post-graduate students, researchers and engineers.
Download or read book First Measurement of the Running of the Top Quark Mass written by Matteo M. Defranchis and published by Springer Nature. This book was released on 2022-01-03 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, the first measurement of the running of the top quark mass is presented. This is a fundamental quantum effect that had never been studied before. Any deviation from the expected behaviour can be interpreted as a hint of the presence of physics beyond the Standard Model. All relevant aspects of the analysis are extensively described and documented. This thesis also describes a simultaneous measurement of the inclusive top quark-antiquark production cross section and the top quark mass in the simulation. The measured cross section is also used to precisely determine the values of the top quark mass and the strong coupling constant by comparing to state-of-the-art theoretical predictions. All the theoretical and experimental aspects relevant to the results presented in this thesis are discussed in the initial chapters in a concise but complete way, which makes the material accessible to a wider audience.
Download or read book Radiative Corrections Status And Outlook Proceedings Of The Tennessee International Symposium written by Bennie F L Ward and published by World Scientific. This book was released on 1995-05-31 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the state of the art and the outlook for the theoretical and experimental aspects of radiative corrections to the SU2L x U₁ x SUc₃3 Standard Model (SM) of elementary particle physics. Particular emphasis is given to SM tests in high precision Z° physics and high energy hadron collider physics.
Download or read book Astroparticle Particle Space Physics And Detectors For Physics Applications Proceedings Of The 13th Icatpp Conference written by Randal C Ruchti and published by World Scientific. This book was released on 2012-08-02 with total page 1100 pages. Available in PDF, EPUB and Kindle. Book excerpt: The exploration of the subnuclear world is done through increasingly complex experiments covering a wide range of energy and performed in a large variety of environments ranging from particle accelerators, underground detectors to satellites and the space laboratory. Among recent advances one has to indicate, for instance, first results obtained from space and LHC experiments and progress done in preparation of the latter experiments upgrades, including plans for the LHC machine upgrade. The achievement of these research programs calls for novel techniques, new materials and instrumentation to be used in detectors, often of large scale. Therefore, fundamental physics is at the forefront of technological advance and also leads to many applications. Among these, medical applications have a particular importance due to health and social benefits they bring to the public.
Download or read book A Measurement of the Mass of the Top Quark in Lepton Jets Events at CDF written by Erik Matthews Brubaker and published by . This book was released on 2004 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hadron Collider Physics 2002 written by Martin Erdmann and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 533 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hadron colliders probe physics at new energy frontiers and search for new particles and forces. In addition, hadron colliders now provide also an environment for precision physics. The present volume collects the results from recently completed runs at major colliders as well as new ideas about collider physics and techniques. It will serve as the main source of reference in the field for many years to come.
Download or read book Lepton Photon Interactions At High Energies Lepton Photon 2017 Proceedings Of The 28th International Symposium written by Wei Wang and published by World Scientific. This book was released on 2020-02-27 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book The Experimental Foundations of Particle Physics written by Robert N. Cahn and published by Cambridge University Press. This book was released on 2009-07-23 with total page 567 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our current understanding of elementary particles and their interactions emerged from break-through experiments. This book presents these experiments, beginning with the discoveries of the neutron and positron, and following them through mesons, strange particles, antiparticles, and quarks and gluons. This second edition contains new chapters on the W and Z bosons, the top quark, B-meson mixing and CP violation, and neutrino oscillations. This book provides an insight into particle physics for researchers, advanced undergraduate and graduate students. Throughout the book, the fundamental equations required to understand the experiments are derived clearly and simply. Each chapter is accompanied by reprinted articles and a collection of problems with a broad range of difficulty.
Download or read book Cracking the Quantum Code of the Universe written by John Moffat and published by Oxford University Press. This book was released on 2014-02 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: If the new boson is indeed the Higgs particle, its discovery represents an important milestone in the history of particle physics. However, despite the pressure to award Nobel Prizes to physicists associated with the Higgs boson, John Moffat argues that there still remain important data analyses to be performed before uncorking the champagne. John Moffat is Professor Emeritus of Physics at the University of Toronto and a senior researcher at the Perimeter Institute for Theoretical Physics. Well-known for his outside-the-box research on topics such as dark matter, dark energy, and the varying speed of light cosmology (VSL), his new book takes a critical look at the hype surrounding the Higgs boson. In the process, he presents a cogent and often entertaining history of particle physics and an exploration of alternative theories of particle physics that do not feature the Higgs boson, including his own. He gives a detailed and personal description of how theoretical physicists come up with new theories, and emphasizes how carefully experimental physicists must interpret the complex data now coming out of accelerators like the Large Hadron Collider (LHC). The book does not shy away from controversial topics such as the sociology of particle physics. There is immense pressure on projects like the $9 billion LHC to come up with positive results in order to secure funding for the future. Yet to date, the Higgs boson may be the only positive result to emerge from the LHC experiments. The searches for dark matter particles, mini-black holes, extra dimensions, and supersymmetric particles have all come up empty-handed, with serious consequences for theoretical physics, including string theory and gravity theory. John Moffat is also the author of Reinventing Gravity (2008) and Einstein Wrote Back (2010).
Download or read book Cpt And Lorentz Symmetry Proceedings Of The Eighth Meeting On Cpt And Lorentz Symmetry written by Ralf Lehnert and published by World Scientific. This book was released on 2020-04-04 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the Proceedings of the Eighth Meeting on CPT and Lorentz Symmetry, held at Indiana University in Bloomington on May 12-16, 2019. The Meeting focused on tests of these fundamental symmetries and on related theoretical issues, including scenarios for possible violations. Topics covered at the meeting include experimental and observational searches for CPT and Lorentz violation involving: accelerators and colliders; astrophysical birefringence, dispersion, and anisotropy; atomic and molecular spectroscopy; cavities, oscillators, resonators; Cherenkov radiation; clock-comparison measurements; CMB polarimetry; cosmic rays; decays of atoms, nuclei, and particles; equivalence-principle tests with matter and antimatter; exotic atoms, muonium, positronium; gauge bosons, the Higgs boson; gravimetry; gravitational waves; high-energy astrophysical observations; hydrogen and antihydrogen spectroscopy; lasers, masers; matter-wave interferometry; meson and baryon properties; neutral-meson interferometry; neutrino mixing and propagation, neutrino-antineutrino oscillations; particle-antiparticle comparisons; photon and particle scattering; post-Newton gravity in the solar system and beyond; second- and third-generation particles; short-range gravity; sidereal and annual time variations, compass asymmetries; single-top and top pair production; space-based missions; spin-gravity couplings; spin precession; time-of-flight measurements; torsion and nonmetricity; trapped particles, ions, and atoms. The meeting also covered theoretical and phenomenological studies of CPT and Lorentz violation including: physical effects at the level of the Standard Model, General Relativity, and beyond; origins and mechanisms for violations; classical and quantum field theory, gravitation, particle physics, and strings; mathematical foundations, Finsler geometry.
