Download or read book Searches for New Physics at Colliders written by My Phuong Thi Le and published by Stanford University. This book was released on 2011 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: The turning-on of the Large Hadron Collider is the momentous milestone in our quest for new physics beyond the Standard Model. Soon, we will be presented with the task of detecting, identifying, and studying the possibly large parameter space of the underlying model. In this thesis, we will look at some possible extensions to the SM, their signatures at colliders, and possible search strategies to explore the new physics in a model-independent way. In chapter 2, we study the extended neutral gauge sector of the Littlest Higgs model at the 500 GeV e+e- collider using the fermion pair production and Higgs associate production channel. We find that these channels can provide an accurate determination of the fundamental parameters and thus allows the verification of the little Higgs mechanism designed to cancel the Higgs mass quadratic divergence. In chapter 3, we study the ATLAS supersymmetry searches proposed for the 14 TeV pp collider using the $\sim$ 70k models of the phenomenological Minimal Supersymmetric Model (pMSSM) moldel set, that have survived many theoretical and experimental constraints. Since pMSSM does not make any simplifying assumptions about its SUSY-breaking mechanism at high scale, this encompasses a broad class of Supersymmetric models. We find that even though these searches were optimized mostly for mSUGRA signals, they are relatively robust in observing the more general pMSSM models. For the case of models in which squarks and gluinos have mass below 1 TeV, essentially all of these models ($> 99\%$) were observable in at least one of these searches, with 1 $fb^{-1}$ of integrated luminosity allowing for an uncertainty of 50\% in the SM background. We found that 0-lepton searches are the most powerful searches, while searches with 1-2 leptons do not have coverage as good as has been shown for mSUGRA. We then study possible reasons why a model could not be observed. These difficult models mostly include those with long-lived charginos which lead to small Missing Tranverse Energy (MET) and models with squeezed spectra which lead to soft jets that fail the jet cuts. In chapter 4, we study similar searches that have been carried out by ATLAS at the 7 TeV LHC. We found that systematic uncertainty again plays an important role in determining the coverage of the searches. This is especially true for searches with a large SM background, such as $n$-jet 0 lepton searches. We study the implication of a null result from the 7 TeV LHC. We find that the degree of fine-tuning in the pMSSM depends on the prior in which we scan our 19-dimensional space, but overall it is not as large as in mSUGRA. We find that a null result at the 7 TeV with $10 fb^{-1}$ and 20\% systematic errors would imply a need for a higher energy e+e- machine than the 500 GeV ILC to study Supersymmetry. Continuing on along the line of Supersymmetry, in chapter 5 we explore the possibility of adding one more generation to the MSSM (4GMSSM). We find that the CP-odd A boson can be very light due to the contribution of the heavy 4th generation fermion loops while all other Higgs particles (including the CP-even {\it h}) are all quite heavy. The parameter $tan(\beta)$ is strongly constrained to be between 0.5 and 2 due to perturbativity requirements on Yukawa couplings. We study the electroweak constraints as well as collider signatures on the possibility of a light A of mass $\sim$115 GeV. As for an LHC discovery, we find that this light A can be seen in the standard 2-photon Higgs search channel with cross-section more than an order of magnitude greater than that of the SM Higgs. In the last two chapters, we study possible search strategies to explore the new physics in a model-independent way. In chapter 6, we attempt to show how one could be largely agnostic about the underlying model in exploring the complete kinematically-allowed parameter space of pair-produced color octet particles (with mass $m_{\tilde{g}}$) that each directly decay into two jets plus a neutral stable particle (with mass $m_{\tilde{B}}$) that would escape the detectors and appear as MET. The kinematics of this process can be completely described by two parameters $m_{\tilde {g}}$ and $m_{\tilde {B}}$ , and in particular their splitting determines the softness or hardness of jets from the decay products. In order to cover the whole parameter space, one would need separate searches for different regions. We show that optimizing the final cuts for every ($m_{\tilde {g}}$, $m_{\tilde {B}}$) point, and combining all searches, can extend the coverage significantly. Since this is just based on the kinematics of the decay, this result can be easily interpreted for any model with this decay topology. In chapter 7, we carry this model-independent approach further in jets plus missing energy searches, by proposing that one should bin the measured data (or simulated SM background) differentially in MET and $H_T$ (scalar sum of invisible energy) for each search, and use them to set limits on any model of interest. We demonstrate this technique by carrying out a search similar to that studied in chapter 6, with one added decay step for the color octet particle, mainly it decays to 2 jets and another particle (with mass $m_{\tilde {W}}$) and it in turn decays to the neutral stable particle and 2 jets. We study different kinematic regions and set bounds in this 3-dimensional parameter space ($m_{\tilde {g}}$, $m_{\tilde {W}}$, $m_{\tilde {B}}$).
Download or read book Collider written by Paul Halpern and published by John Wiley & Sons. This book was released on 2009-08-03 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: An accessible look at the hottest topic in physics and the experiments that will transform our understanding of the universe The biggest news in science today is the Large Hadron Collider, the world's largest and most powerful particle-smasher, and the anticipation of finally discovering the Higgs boson particle. But what is the Higgs boson and why is it often referred to as the God Particle? Why are the Higgs and the LHC so important? Getting a handle on the science behind the LHC can be difficult for anyone without an advanced degree in particle physics, but you don't need to go back to school to learn about it. In Collider, award-winning physicist Paul Halpern provides you with the tools you need to understand what the LHC is and what it hopes to discover. Comprehensive, accessible guide to the theory, history, and science behind experimental high-energy physics Explains why particle physics could well be on the verge of some of its greatest breakthroughs, changing what we think we know about quarks, string theory, dark matter, dark energy, and the fundamentals of modern physics Tells you why the theoretical Higgs boson is often referred to as the God particle and how its discovery could change our understanding of the universe Clearly explains why fears that the LHC could create a miniature black hole that could swallow up the Earth amount to a tempest in a very tiny teapot "Best of 2009 Sci-Tech Books (Physics)"-Library Journal "Halpern makes the search for mysterious particles pertinent and exciting by explaining clearly what we don't know about the universe, and offering a hopeful outlook for future research."-Publishers Weekly Includes a new author preface, "The Fate of the Large Hadron Collider and the Future of High-Energy Physics" The world will not come to an end any time soon, but we may learn a lot more about it in the blink of an eye. Read Collider and find out what, when, and how.
Download or read book Indirect Searches for New Physics written by Alexey A. Petrov and published by CRC Press. This book was released on 2021-05-04 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first book to discuss the search for new physics in charged leptons, neutrons, and quarks in one coherent volume. The area of indirect searches for new physics is highly topical; though no new physics particles have yet been observed directly at the Large Hadron Collider at CERN, the methods described in this book will provide researchers with the necessary tools to keep searching for new physics. It describes the lines of research that attempt to identify quantum effects of new physics particles in low-energy experiments, in addition to detailing the mathematical basis and theoretical and phenomenological methods involved in the searches, whilst making a clear distinction between model-dependent and model-independent methods employed to make predictions. This book will be a valuable guide for graduate students and early-career researchers in particle and high energy physics who wish to learn about the techniques used in modern predictions of new physics effects at low energies, whilst also serving as a reference for researchers at other levels. Key features: • Takes an accessible, pedagogical approach suitable for graduate students and those seeking an overview of this new and fast-growing field • Illustrates common theoretical trends seen in different subfields of particle physics • Valuable both for researchers in the phenomenology of elementary particles and for experimentalists
Download or read book Aspects of WIMP Dark Matter Searches at Colliders and Other Probes written by Enrico Morgante and published by Springer. This book was released on 2017-10-05 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis covers several theoretical aspects of WIMP (weakly interacting massive particles) dark matter searches, with a particular emphasis on colliders. It mainly focuses on the use of effective field theories as a tool for Large Hadron Collider (LHC) searches, discussing in detail the issue of their validity, and on simplified dark matter models, which are receiving a growing attention from the physics community. It highlights the theoretical consistency of simplified models, which is essential in order to correctly exploit their potential and for them to be a common reference when comparing results from different experiments. This thesis is of interest to researchers (both theorists and experimentalists) in the field of dark matter searches, and offers a comprehensive introduction to dark matter and to WIMP searches for students and non-experts.
Download or read book Anomaly Collider Physics And The Quest For New Phenomena At Fermilab written by Dorigo Tommaso and published by World Scientific. This book was released on 2016-09-26 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the mid-1980s, an international collaboration of 600 physicists embarked on the investigation of subnuclear physics at the high-energy frontier. As well as discovering the top quark, the heaviest elementary particle ever observed, the physicists analyzed their data to seek signals of new physics which could revolutionize our understanding of nature. Anomaly! tells the story of that quest, and focuses specifically on the finding of several unexplained effects which were unearthed in the process. These anomalies proved highly controversial within the large team: to some collaborators they called for immediate publication, while to others their divulgation threatened to jeopardize the reputation of the experiment. Written in a confidential, narrative style, this book looks at the sociology of a large scientific collaboration, providing insight in the relationships between top physicists at the turn of the millennium. The stories offer an insider's view of the life cycle of the "failed" discoveries that unavoidably accompany even the greatest endeavors in modern particle physics.
Download or read book Hadron Collider Physics Proceedings Of The Xi Symposium written by D Bisello and published by World Scientific. This book was released on 1997-06-01 with total page 814 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proceedings of this series of annual symposia represent an extensive summary of the experimental and theoretical status of high energy physics at hadron colliders. This volume discusses the latest results on top and beauty physics, QCD, electroweak physics and searches for new particles. The prospects of this field for LHC, Tevatron and Hera machines are also reported.
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 QCD and Collider Physics written by R. K. Ellis and published by Cambridge University Press. This book was released on 2003-12-04 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed overview of the physics of high-energy colliders emphasising the role of QCD.
Download or read book Perspectives on Lhc Physics written by G. L. Kane and published by World Scientific. This book was released on 2008 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Large Hadron Collider (LHC), located at CERN, Geneva, Switzerland, is the world's largest and highest energy and highest intensity particle accelerator. Here is a timely book with several perspectives on the hoped-for discoveries from the LHC.This book provides an overview on the techniques that will be crucial for finding new physics at the LHC, as well as perspectives on the importance and implications of the discoveries. Among the accomplished contributors to this book are leaders and visionaries in the field of particle physics beyond the Standard Model, including two Nobel Laureates (Steven Weinberg and Frank Wilczek), and presumably some future Nobel Laureates, plus top younger theorists and experimenters. With its blend of popular and technical contents, the book will have wide appeal, not only to physical scientists but also to those in related fields.
Download or read book Search for New Physics in tt Final States with Additional Heavy Flavor Jets with the ATLAS Detector written by Javier Montejo Berlingen and published by Springer. This book was released on 2016-07-20 with total page 283 pages. Available in PDF, EPUB and Kindle. Book excerpt: This doctoral thesis focuses on the search for new phenomena in top-antitop quark (tt) final states with additional b-quark jets at the LHC. It uses the full Run 1 dataset collected by the ATLAS experiment in proton-proton collisions at √s=8 TeV. The final state of interest consists of an isolated lepton, a neutrino and at least six jets with at least four b-tagged jets, a challenging experimental signature owing to the large background from tt+heavy-flavor production. This final state is characteristic of ttH production, with the Higgs boson decaying into bb, a process that allows direct probing of the top-Higgs Yukawa coupling. This signature is also present in many extensions of the Standard Model that have been proposed as solutions to the hierarchy problem, such as supersymmetry or composite Higgs models, which predict the pair production of bosonic or fermionic top quark partners, or the anomalous production of four-top-quark events. All these physics processes have been searched for using an ambitious search strategy that has been developed on the basis of a combination of state-of-art theoretical predictions and a sophisticated statistical analysis to constrain in-situ the large background uncertainties. As a result, the most restrictive bounds to date on the above physics processes have been obtained.
Download or read book Collider Physics written by Vernon D. Barger and published by CRC Press. This book was released on 2018-05-30 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt: This updated edition of Collider Physics surveys the major developments in theoretical and experimental particle physics and uses numerous illustrations to show how the Standard Model explains the experimental results. Collider Physics offers an introduction to the fundamental particles and their interactions at the level of a lecture course for graduate students, with emphasis on the aspects most closely related to colliders--past, present, and future. It includes expectations for new physics associated with Higgs bosons and supersymmetry. This resourceful book shows how to make practical calculations and serves a dual purpose as a textbook and a handbook for collider physics phenomenology.
Download or read book Collider Search at the LHC for New Physics in Electroweak Symmetry Breaking Sector written by Guiyu Huang and published by . This book was released on 2008 with total page 208 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 142 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 The Search and Discovery of the Higgs Boson written by Luis Roberto Flores Castillo and published by Morgan & Claypool Publishers. This book was released on 2016-01-01 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a general description of the search for and discovery of the Higgs boson (particle) at CERN’s Large Hadron Collider. The goal is to provide a relatively brief overview of the issues, instruments and techniques relevant for this search; written by a physicist who was directly involved. The Higgs boson mat be the one particle that was studied the most before its discovery and the story from postulation in 1964 to detection in 2012 is a fascinating one. The story is told here while detailing the fundamentals of particle physics.
Download or read book The Large Hadron Collider written by Lyndon R. Evans and published by EPFL Press. This book was released on 2009-01-01 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the technology and engineering of the Large Hadron collider (LHC), one of the greatest scientific marvels of this young 21st century. This book traces the feat of its construction, written by the head scientists involved, placed into the context of the scientific goals and principles.
Download or read book Electroweak Symmetry Breaking And New Physics At The Tev Scale written by Timothy L Barklow and published by World Scientific. This book was released on 1997-05-05 with total page 749 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an expanded version of the report by the Electroweak Symmetry Breaking and Beyond the Standard Model Working Group which was contributed to Particle Physics — Perspectives and Opportunities, a report of the Division of Particles and Fields Committee for Long Term Planning. One of the Working Group's primary goals was to study the phenomenology of electroweak symmetry breaking and attempt to quantify the “physics reach” of present and future colliders. Their investigations encompassed the Standard Model — with one doublet of Higgs scalars — and approaches to physics beyond the Standard Model. These include models of low-energy supersymmetry, dynamical electroweak symmetry breaking, and a variety of extensions of the Standard Model with new particles and interactions. The Working Group also considered signals of new physics in precision measurements arising from virtual processes and examined experimental issues associated with the study of electroweak symmetry breaking and the search for new physics at present and future hadron and lepton colliders.This volume represents an important contribution to the efforts being made to advance the frontiers of particle physics.
Download or read book Search for the totally Unexpected in the LHC Era written by Antonino Zichichi and published by World Scientific. This book was released on 2010 with total page 511 pages. Available in PDF, EPUB and Kindle. Book excerpt: From 29 August to 7 September 2007, a large group of distinguished lecturers and young physicists from various countries met in Erice, Italy, at the ?Ettore Majorana? Foundation and Centre for Scientific Culture (EMFCSC) to attend the 45th Course of the International School of Subnuclear Physics: ?Search for the ?Totally Unexpected? in the LHC era?.This book is a collection of lectures delivered during the course, which covered the most recent advances in theoretical physics and the latest results from the current experimental facilities. In the School's effort to encourage and promote young physicists achieve recognition at an international level, students who distinguished themselves for the excellence of their research have been given the opportunity to publish their presentation in this volume.
