Beyond Standard Model Collider Phenomenology Of Higgs Physics And Supersymmetry

Author by : Marc Christopher Thomas
Languange : en
Publisher by : Springer
Format Available : PDF, ePub, Mobi
Total Read : 26
Total Download : 805
File Size : 55,7 Mb
GET BOOK

Description : This thesis studies collider phenomenology of physics beyond the Standard Model at the Large Hadron Collider (LHC). It also explores in detail advanced topics related to Higgs boson and supersymmetry – one of the most exciting and well-motivated streams in particle physics. In particular, it finds a very large enhancement of multiple Higgs boson production in vector-boson scattering when Higgs couplings to gauge bosons differ from those predicted by the Standard Model. The thesis demonstrates that due to the loss of unitarity, the very large enhancement for triple Higgs boson production takes place. This is a truly novel finding. The thesis also studies the effects of supersymmetric partners of top and bottom quarks on the Higgs production and decay at the LHC, pointing for the first time to non-universal alterations for two main production processes of the Higgs boson at the LHC–vector boson fusion and gluon–gluon fusion. Continuing the exploration of Higgs boson and supersymmetry at the LHC, the thesis extends existing experimental analysis and shows that for a single decay channel the mass of the top quark superpartner below 175 GeV can be completely excluded, which in turn excludes electroweak baryogenesis in the Minimal Supersymmetric Model. This is a major new finding for the HEP community. This thesis is very clearly written and the introduction and conclusions are accessible to a wide spectrum of readers.


Modern Elementary Particle Physics

Author by : Gordon Kane
Languange : en
Publisher by : Cambridge University Press
Format Available : PDF, ePub, Mobi
Total Read : 13
Total Download : 107
File Size : 47,5 Mb
GET BOOK

Description : This book is written for students and scientists wanting to learn about the Standard Model of particle physics. Only an introductory course knowledge about quantum theory is needed. The text provides a pedagogical description of the theory, and incorporates the recent Higgs boson and top quark discoveries. With its clear and engaging style, this new edition retains its essential simplicity. Long and detailed calculations are replaced by simple approximate ones. It includes introductions to accelerators, colliders, and detectors, and several main experimental tests of the Standard Model are explained. Descriptions of some well-motivated extensions of the Standard Model prepare the reader for new developments. It emphasizes the concepts of gauge theories and Higgs physics, electroweak unification and symmetry breaking, and how force strengths vary with energy, providing a solid foundation for those working in the field, and for those who simply want to learn about the Standard Model.


The Standard Model And Beyond

Author by : Paul Langacker
Languange : en
Publisher by : CRC Press
Format Available : PDF, ePub, Mobi
Total Read : 9
Total Download : 545
File Size : 41,5 Mb
GET BOOK

Description : This new edition of The Standard Model and Beyond presents an advanced introduction to the physics and formalism of the standard model and other non-abelian gauge theories. It provides a solid background for understanding supersymmetry, string theory, extra dimensions, dynamical symmetry breaking, and cosmology. In addition to updating all of the experimental and phenomenological results from the first edition, it contains a new chapter on collider physics; expanded discussions of Higgs, neutrino, and dark matter physics; and many new problems. The book first reviews calculational techniques in field theory and the status of quantum electrodynamics. It then focuses on global and local symmetries and the construction of non-abelian gauge theories. The structure and tests of quantum chromodynamics, collider physics, the electroweak interactions and theory, and the physics of neutrino mass and mixing are thoroughly explored. The final chapter discusses the motivations for extending the standard model and examines supersymmetry, extended gauge groups, and grand unification. Thoroughly covering gauge field theories, symmetries, and topics beyond the standard model, this text equips readers with the tools to understand the structure and phenomenological consequences of the standard model, to construct extensions, and to perform calculations at tree level. It establishes the necessary background for readers to carry out more advanced research in particle physics. Supplementary materials are provided on the author’s website and a solutions manual is available for qualifying instructors.


String Theory And The Real World

Author by : Gordon Kane
Languange : en
Publisher by : Morgan & Claypool Publishers
Format Available : PDF, ePub, Mobi
Total Read : 59
Total Download : 376
File Size : 53,5 Mb
GET BOOK

Description : This book attempts to explain why 'string theory' may provide the comprehensive underlying theory that describes and explains our world. It is an enthusiastic view of how compactified string/M-theories (plus data that may be reachable) seem to have the possibilities of leading to a comprehensive underlying theory of particle physics and cosmology, perhaps soon. We are living in a hugely exciting era for science, one during which it may be possible to achieve a real and true understanding of our physical world.


Physics Beyond The Standard Model

Author by : Anonim
Languange : en
Publisher by : Unknown
Format Available : PDF, ePub, Mobi
Total Read : 93
Total Download : 463
File Size : 55,5 Mb
GET BOOK

Description : The Standard Model (SM) of particle physics is remarkably successful and has survived two decades of precision tests at high energy particle accelerators. However, it is known to be incomplete, and there are reasons to believe that there is new physics at energy scales that will soon be probed in greater detail than ever before by the Large Hadron Collider (LHC), a proton-proton accelerator being built near Geneva. This thesis contains a diverse set of topics that may broadly be described as physics beyond the SM. In Chapter 2, implications of current experimental constraints are presented for the stop masses and mixing in the Minimal Supersymmetric Standard Model (MSSM), a well-motivated candidate for physics beyond the SM. It is found, for example, that lower bounds on the stop masses are as large as 1 TeV assuming no stop-mixing. Chapter 3 presents the regions in the MSSM with the minimal amount of fine-tuning of electroweak symmetry breaking. The minimal amount of tuning increases enormously for a Higgs mass beyond 120 GeV. Supersymmetry cannot be an exact symmetry, and one possibility is that our Universe is in a long-lived metastable state with broken supersymmetry. In Chapter 4, a generic model with this property is constructed in which all the relevant parameters, including the supersymmetry breaking scale, are generated dynamically. This model has several interesting model-building features including an explicitly and spontaneously broken R-symmetry, a singlet, a large global symmetry, naturalness, renormalizability, and a "pseudo-runaway'' direction. In Chapter 5, a simple extension of the SM with weakly interacting non-chiral dark matter particles is presented. Such particles can be detected at a future direct-detection experiment. There are a wide variety of possible discovery signatures for new physics at the LHC. A discovery signature with a large SM background that has not been well studied involves multi-jet events without leptons and/or missing energy. In Chapter 6, it is found that using innovative search strategies pair production of new coloured adjoint fermions producing a pure six-jet final state can be detected up to a mass of about 650-700 GeV with 10 fb-1 of integrated luminosity.


Electroweak Symmetry Breaking And New Physics At The Tev Scale

Author by : Timothy L Barklow
Languange : en
Publisher by : World Scientific
Format Available : PDF, ePub, Mobi
Total Read : 94
Total Download : 245
File Size : 42,9 Mb
GET BOOK

Description : 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. Contents:Electroweak Symmetry Breaking and Physics Beyond the Standard ModelWeakly-Coupled Higgs BosonsImplications of Supersymmetry Model BuildingLow Energy Supersymmetry PhenomenologyStrongly-Interacting Electroweak Sector — Model Independent ApproachesStrongly Coupled Electroweak Symmetry Breaking: Implications of ModelsDiscovery and Identification of Extra Gauge BosonsNew Particles and InteractionsAnomalous Gauge Boson InteractionsIndirect Probes of New PhysicsExperimental Issues at Hadron CollidersExperimental Issues at e+e- Linear Colliders Readership: Graduates and researchers in high energy physics. keywords:Electroweak Symmetry Breaking;TeV Scale;Higgs Boson;Supersymmetry;Hadron Collider;Linear Collider;Gauge Boson;Beyond the Standard Model;Dynamical Symmetry Breaking;High Energy Physics


Searches For New Physics At Colliders

Author by : Anonim
Languange : en
Publisher by : Stanford University
Format Available : PDF, ePub, Mobi
Total Read : 28
Total Download : 719
File Size : 40,6 Mb
GET BOOK

Description : 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


Large Hadron Collider Phenomenology

Author by : M. Kramer
Languange : en
Publisher by : CRC Press
Format Available : PDF, ePub, Mobi
Total Read : 13
Total Download : 148
File Size : 49,8 Mb
GET BOOK

Description : With the Large Hadron Collider (LHC) under construction and due to come online in 2007, it is appropriate to engage in a focused review on LHC phenomenology. At a time when most of the experimental effort is centered on detector construction and software development, it is vitally important to direct the experimental community and, in particular, new researchers on the physics phenomena expected from the LHC. Large Hadron Collider Phenomenology covers the capabilities of LHC, from searches for the Higgs boson and physics beyond the standard model to detailed studies of quantum chromodynamics, the B-physics sectors, and the properties of hadronic matter at high energy density as realized in heavy-ion collisions. Written by experienced researchers and experimentalists, this reference examines the basic properties and potentials of the machine, detectors, and software required for physics analyses. The book starts with a basic introduction to the standard model and its applications to the phenomena observed at high energy collisions. Later chapters describe the key technological challenges facing the construction of the LHC machine, the operating detectors of the LHC, and the vast computing grid needed to analyze the data. In the final sections, the contributors discuss the quark-gluon plasma (QGP), explore questions and predictions for the LHC program, and examine the physics opportunities of the LHC using information from the forward region. By surveying the difficult challenges of the LHC development while also assessing the novel processes that the LHC will perform, Large Hadron Collider Phenomenology aids less seasoned physicists as well as existing researchers in discovering the numerous possibilities of the LHC.


String Theory And The Real World

Author by : Gordon Kane
Languange : en
Publisher by : Iop Concise Physics
Format Available : PDF, ePub, Mobi
Total Read : 61
Total Download : 860
File Size : 43,5 Mb
GET BOOK

Description : This book attempts to explain why 'string theory' may provide the comprehensive underlying theory that describes and explains our world. It is an enthusiastic view of how compactified string/M-theories (plus data that may be reachable) seem to have the possibilities of leading to a comprehensive underlying theory of particle physics and cosmology, perhaps soon. We are living in a hugely exciting era for science, one during which it may be possible to achieve a real and true understanding of our physical world.


Beyond The Standard Model Of Elementary Particle Physics

Author by : Yorikiyo Nagashima
Languange : en
Publisher by : John Wiley & Sons
Format Available : PDF, ePub, Mobi
Total Read : 90
Total Download : 893
File Size : 51,8 Mb
GET BOOK

Description : A unique and comprehensive presentation on modern particle physics which stores the background knowledge on the big open questions beyond the standard model, as the existence of the Higgs-boson, or the nature of Dark Matter and Dark Energy.


Introduction To The Standard Model And Beyond

Author by : Stuart Raby
Languange : en
Publisher by : Cambridge University Press
Format Available : PDF, ePub, Mobi
Total Read : 65
Total Download : 579
File Size : 41,5 Mb
GET BOOK

Description : The Standard Model of particle physics is an amazingly successful theory describing the fundamental particles and forces of nature. This text, written for a two-semester graduate course on the Standard Model, develops a practical understanding of the theoretical concepts it's built upon, to prepare students to enter research. The author takes a historical approach to demonstrate to students the process of discovery which is often overlooked in other textbooks, presenting quantum field theory and symmetries as the necessary tools for describing and understanding the Standard Model. He develops these tools using a basic understanding of quantum mechanics and classical field theory, such as Maxwell's electrodynamics, before discussing the important role that Noether's theorem and conserved charges play in the theory. Worked examples feature throughout the text, while homework exercises are included for the first five parts, with solutions available online for instructors. Inspired by the author's own teaching experience, suggestions for independent research topics have been provided for the second-half of the course, which students can then present to the rest of the class.


Dawn Of The Lhc Era The Tasi 2008 Proceedings Of The 2008 Theoretical Advanced Study Institute In Elementary Particle Physics

Author by : Tao Han
Languange : en
Publisher by : World Scientific
Format Available : PDF, ePub, Mobi
Total Read : 93
Total Download : 956
File Size : 52,6 Mb
GET BOOK

Description : This book contains material from the lecture courses conducted at the Theoretical Advanced Study Institute (TASI, Colorado, USA) on high energy physics and cosmology in 2008. Three series of lectures are presented in parallel in the areas of Large Hadron Collider (LHC) phenomenology and experimentation; advanced theoretical topics beyond the standard model; and neutrino oscillation, astroparticle physics and cosmology. The phenomenology lectures cover a broad spectrum of standard research techniques used to interpret present-day and LHC data. The new physics lectures focus on modern speculations about physics beyond the standard model, with an emphasis on supersymmetry, grand unification theories, extra-dimensional theories, and string phenomenology, which may be tested at the LHC. The lecture series on neutrino physics, astroparticle physics and cosmology treats recent developments in neutrino oscillations, theories and searches of dark matter and dark energy, cosmic microwave background radiation, and density perturbation theory. The lectures are of pedagogical nature in presentation, and are accessible to advanced graduate students and researchers in high energy physics and cosmology.


Colliders And Neutrinos The Window Into Physics Beyond The Standard Model Tasi 2006

Author by : Sally Dawson
Languange : en
Publisher by : World Scientific
Format Available : PDF, ePub, Mobi
Total Read : 58
Total Download : 451
File Size : 42,6 Mb
GET BOOK

Description : This book is a collection of theoretical advanced summer institute lectures by world experts in the field of collider physics and neutrinos, the two frontier areas of particle physics today. It is aimed at graduate students and beginning researchers, and as such, provides many pedagogical details not generally available in standard conference proceedings.


Beyond Standard Model Phenomenology At The Lhc

Author by : Priscila de Aquino
Languange : en
Publisher by : Springer Science & Business Media
Format Available : PDF, ePub, Mobi
Total Read : 70
Total Download : 695
File Size : 40,8 Mb
GET BOOK

Description : This thesis provides an introduction to the physics of the Standard Model and beyond, and to the methods used to analyse Large Hadron Collider (LHC) data. The 'hierarchy problem', astrophysical data and experiments on neutrinos indicate that new physics can be expected at the now accessible TeV scale. This work investigates extensions of the Standard Model with gravitons and gravitinos (in the context of supergravity). The production of these particles in association with jets is studied as one of the most promising avenues for researching new physics at the LHC. Advanced simulation techniques and tools, such as algorithms allowing the computation of Feynman graphs and helicity amplitudes are first developed and then employed.


The Standard Model And Beyond

Author by : Jihn E Kim
Languange : en
Publisher by : World Scientific
Format Available : PDF, ePub, Mobi
Total Read : 90
Total Download : 198
File Size : 44,7 Mb
GET BOOK

Description : The most recent LEP data is included in the lectures. The subjects include Higgs physics, KM angles, weak CP violation, neutron electric dipole moment, SUSY phenomenology, radiative corrections, and e+e- experiments. Contents:Introduction to the Standard Model and Neutral Currents (J E Kim)Higgs Physics: Theory and Phenomenology (H E Haber)Weak Flavor Physics (C S Kim)Mechanisms of CP Violation in Gauge Theory and the Recent Developments (D Chang)Chiral Dynamics and Flavor Conserving CP Violation (K Choi)An Introduction to Supersymmetry and Supersymmetry Phenomenology (X Tata) e+e- Physics (D Son) Readership: High energy and nuclear physicists and cosmologists. keywords:


Particle Physics And Cosmology The Quest For Physics Beyond The Standard Model S Tasi 2002

Author by : Howard E Haber
Languange : en
Publisher by : World Scientific
Format Available : PDF, ePub, Mobi
Total Read : 12
Total Download : 470
File Size : 51,8 Mb
GET BOOK

Description : This book contains the lecture courses conducted at the School of the Theoretical Advanced Study Institute (TASI, Colorado, USA) on Elementary Particle Physics in 2002. In this School, three series of lectures are presented in parallel in the area of phenomenology, TeV-scale physics, and astroparticles physics. The phenomenology lecture series covered a broad spectrum of standard research techniques used to interpret present day and future collider data. The TeV-scale physics lecture series focused on modern speculations about physics beyond the Standard Model, with an emphasis on supersymmetry and extra-dimensional theories. The lecture series on astroparticle physics treated recent developments in theories of dark matter and dark energy, the cosmic microwave background, and prospects for the upcoming era of gravitational wave astronomy.


Nuclear And Particle Physics

Author by : Brian R. Martin
Languange : en
Publisher by : John Wiley & Sons
Format Available : PDF, ePub, Mobi
Total Read : 33
Total Download : 229
File Size : 41,6 Mb
GET BOOK

Description : Updated and expanded edition of this well-known Physics textbook provides an excellent Undergraduate introduction to the field This new edition of Nuclear and Particle Physics continues the standards established by its predecessors, offering a comprehensive and highly readable overview of both the theoretical and experimental areas of these fields. The updated and expanded text covers a very wide range of topics in particle and nuclear physics, with an emphasis on the phenomenological approach to understanding experimental data. It is one of the few publications currently available that gives equal treatment to both fields, while remaining accessible to undergraduates. Early chapters cover basic concepts of nuclear and particle physics, before describing their respective phenomenologies and experimental methods. Later chapters interpret data through models and theories, such as the standard model of particle physics, and the liquid drop and shell models of nuclear physics, and also discuss many applications of both fields. The concluding two chapters deal with practical applications and outstanding issues, including extensions to the standard model, implications for particle astrophysics, improvements in medical imaging, and prospects for power production. There are a number of useful appendices. Other notable features include: New or expanded coverage of developments in relevant fields, such as the discovery of the Higgs boson, recent results in neutrino physics, research to test theories beyond the standard model (such as supersymmetry), and important technical advances, such as Penning traps used for high-precision measurements of nuclear masses. Practice problems at the end of chapters (excluding the last chapter) with solutions to selected problems provided in an appendix, as well as an extensive list of references for further reading. Companion website with solutions (odd-numbered problems for students, all problems for instructors), PowerPoint lecture slides, and other resources. As with previous editions, the balanced coverage and additional resources provided, makes Nuclear and Particle Physics an excellent foundation for advanced undergraduate courses, or a valuable general reference text for early graduate studies.


Supersymmetry Supergravity And Superstring Proceedings Of The Kias Ctp International Symposium

Author by : Kim Jihn E
Languange : en
Publisher by : World Scientific
Format Available : PDF, ePub, Mobi
Total Read : 76
Total Download : 250
File Size : 47,6 Mb
GET BOOK

Description : Supersymmetry, supergravity and superstring are the most popular research topics in particle physics. In particular, the phenomenological studies beyond the standard model have become very popular in view of possible identification or exclusion of supersymmetric particles in the future. Also, the lightest supersymmetric particle in most supersymmetric models can be a good candidate for dark matter in the universe.The recent developments in supersymmetry with important applications to particle physics are the main theme of this book, which includes superstring calculations with D-branes, TeV-scale gravity, superstring- and supergravity-inspired interactions, supersymmetric GUT, supergravity phenomenology, and cosmological implications of LSP.


Distinguishing Models Of New Physics At The Lhc

Author by : Patrik Svantesson
Languange : en
Publisher by : Unknown
Format Available : PDF, ePub, Mobi
Total Read : 79
Total Download : 883
File Size : 52,5 Mb
GET BOOK

Description : The work presented in this thesis explores ways of distinguishing models of physics beyond the Standard Model at the Large Hadron Collider (LHC). The focus is put on supersymmetric models, in particular the Minimal Supersymmetric Standard Model (MSSM) and the E6-inspired Supersymmetric Standard Model (E6SSM), which are well known and well motivated models. The muon decay channel of the pseudoscalar and heavy Higgs bosons in the MSSM is studied. It is shown that these decays to muons, in some scenarios, make it possible to measure the widths of these Higgs bosons at the LHC. This is the only known way of measuring this width at the LHC. The decays to muons also allow for the mass to be measured accurately which together with the width measurement offers a unique opportunity to pin down the value of the model parameter tan Beta, which could be used to distinguish different scenarios within the MSSM and potentially in its extensions. Gluino cascade decays are investigated as a tool to distinguish the MSSM from more complex models, with the E6SSM as an example. It is shown that the longer cascade decays of the E6SSM gluinos provide less missing transverse momentum and higher lepton multiplicity, implying the higher importance of multi-lepton searches at the LHC in models with a richer low-energy particle content. The three-lepton channel is shown to be a good discriminator between the models. In the case of a gluino discovery one would typically expect a signal in this channel if it is an E6SSM gluino but not if it is an MSSM gluino. Furthermore, the implications of limits from dark matter and Z' searches on the Higgs sector and other collider phenomenology are discussed. These implications are important to constrain and differentiate models. In addition, the contribution to fine-tuning from the Z' mass is discussed as an important measure of how attractive a model is, which should be considered by model builders.


Particle Physics Beyond The Standard Model

Author by : Anonim
Languange : en
Publisher by : Elsevier
Format Available : PDF, ePub, Mobi
Total Read : 99
Total Download : 582
File Size : 53,5 Mb
GET BOOK

Description : The Standard Model of elementary particles and interactions is one of the best tested theories in physics. It has been found to be in remarkable agreement with experiment, and its validity at the quantum level has been successfully probed in the electroweak sector. In spite of its experimental successes, though, the Standard Model suffers from a number of limitations, and is likely to be an incomplete theory. It contains many arbitrary parameters; it does not include gravity, the fourth elementary interaction; it does not provide an explanation for the hierarchy between the scale of electroweak interactions and the Planck scale, characteristic of gravitational interactions; and finally, it fails to account for the dark matter and the baryon asymmetry of the universe. This led particle theorists to develop and study various extensions of the Standard Model, such as supersymmetric theories, Grand Unified Theories or theories with extra space-time dimensions - most of which have been proposed well before the experimental verification of the Standard Model. The coming generation of experimental facilities (such as high-energy colliders, B-physics experiments, neutrino superbeams, as well as astrophysical and cosmological observational facilities) will allow us to test the predictions of these theories and to deepen our understanding of the fundamental laws of nature. This book is a collection of lectures given in August 2005 at the Les Houches Summer School on Particle Physics beyond the Standard Model. It provides a pedagogical introduction to the various aspects of particle physics beyond the Standard Model, covering each topic from the basics to the most recent developments: supersymmetric theories, Grand Unified Theories, theories with extra dimensions, flavour physics and CP violation, neutrino physics, astroparticle physics and cosmology. · Provides a pedagogical introduction to particle physics beyond the Standard Model · Covers the various aspects of particle physics beyond the Standard Model · Addresses each topic from the basics to the most recent developments · Addresses both the theoretical and phenomenological aspects of the subject · Written in a pedagogical style by leading experts in the field


Perspectives On String Phenomenology

Author by : Bobby Acharya
Languange : en
Publisher by : World Scientific
Format Available : PDF, ePub, Mobi
Total Read : 45
Total Download : 576
File Size : 55,6 Mb
GET BOOK

Description : The remarkable recent discovery of the Higgs boson at the CERN Large Hadron Collider completed the Standard Model of particle physics and has paved the way for understanding the physics which may lie beyond it. String/M theory has emerged as a broad framework for describing a plethora of diverse physical systems, which includes condensed matter systems, gravitational systems as well as elementary particle physics interactions. If string/M theory is to be considered as a candidate theory of Nature, it must contain an effectively four-dimensional universe among its solutions that is indistinguishable from our own. In these solutions, the extra dimensions of string/M theory are “compactified” on tiny scales which are often comparable to the Planck length. String phenomenology is the branch of string/M theory that studies such solutions, relates their properties to data, and aims to answer many of the outstanding questions of particle physics beyond the Standard Model. This book contains perspectives on string phenomenology from some of the leading experts in the field. Contributions will range from pedagogical general overviews and perspectives to more technical reviews. We hope that the reader will get a sense of the significant progress that has been made in the field in recent years (e.g. in the topic of moduli stabilization) as well as the topics currently being researched, outstanding problems and some perspectives for the future. Contents:PrefaceAcknowledgmentsWhat is an Electroon? (M J Perry)The What and Why of Moduli (J Conlon)Perspective on the Weakly Coupled Heterotic String (M K Gaillard)Geography of Fields in Extra Dimensions: String Theory Lessons for Particle Physics (H P Nilles & P K S Vaudrevange)The String Landscape: A Personal Perspective (K R Dienes)Mathematics for String Phenomenology (M R Douglas)The String Theory Landscape (A N Schellekens)Local String Models and Moduli Stabilization (F Quevedo)F-Theory: From Geometry to Phenomenology (S Schaefer-Nameki)Compactified String Theories — Generic Predictions for Particle Physics (P Kumar)How Could (Should) We Make Contact Between String/M Theory and Our Four-Dimensional World? (G Kane)String Cosmology — Large-Field Inflation in String Theory (A Westphal)Dark Energy in String Theory (B Greene & G Shiu)Cosmological SUSY Breaking and the Pyramid Scheme (T Banks) Readership: Physicists and graduates interested in string theory. Keywords:String Theory;M-Theory;String Phenomenology;Compactified String Theory;String Cosmology


Radiative Corrections Radcor 98 Application Of Quantum Field Theory To Phenomenology Proceedings Of 4th

Author by : Sola Joan
Languange : en
Publisher by : World Scientific
Format Available : PDF, ePub, Mobi
Total Read : 15
Total Download : 673
File Size : 40,9 Mb
GET BOOK

Description : This volume contains the proceedings of the GDH 2002 symposium. It is a review of the most recent results on the nucleon spin structure and related sum rules using real and virtual photons. The latest theoretical developments and the new high precision data from different laboratories are presented and discussed. The book provides a comprehensive picture of the nucleon spin studies from the perturbative domain down to the resonance and low momentum transfer region.


The Beyond The Standard Model Working Group

Author by : Anonim
Languange : en
Publisher by : Unknown
Format Available : PDF, ePub, Mobi
Total Read : 75
Total Download : 407
File Size : 55,5 Mb
GET BOOK

Description : In this working group we have investigated a number of aspects of searches for new physics beyond the Standard Model (SM) at the running or planned TeV-scale colliders. For the most part, we have considered hadron colliders, as they will define particle physics at the energy frontier for the next ten years at least. The variety of models for Beyond the Standard Model (BSM) physics has grown immensely. It is clear that only future experiments can provide the needed direction to clarify the correct theory. Thus, our focus has been on exploring the extent to which hadron colliders can discover and study BSM physics in various models. We have placed special emphasis on scenarios in which the new signal might be difficult to find or of a very unexpected nature. For example, in the context of supersymmetry (SUSY), we have considered: how to make fully precise predictions for the Higgs bosons as well as the superparticles of the Minimal Supersymmetric Standard Model (MSSM) (parts III and IV); MSSM scenarios in which most or all SUSY particles have rather large masses (parts V and VI); the ability to sort out the many parameters of the MSSM using a variety of signals and study channels (part VII); whether the no-lose theorem for MSSM Higgs discovery can be extended to the next-to-minimal Supersymmetric Standard Model (NMSSM) in which an additional singlet superfield is added to the minimal collection of superfields, potentially providing a natural explanation of the electroweak value of the parameter [mu] (part VIII); sorting out the effects of CP violation using Higgs plus squark associate production (part IX); the impact of lepton flavor violation of various kinds (part X); experimental possibilities for the gravitino and its sgoldstino partner (part XI); what the implications for SUSY would be if the NuTeV signal for di-muon events were interpreted as a sign of R-parity violation (part XII). Our other main focus was on the phenomenological implications of extra dimensions. There, we considered: constraints on Kaluza Klein (KK) excitations of the SM gauge bosons from existing data (part XIII) and the corresponding projected LHC reach (part XIV); techniques for discovering and studying the radion field which is generic in most extra-dimensional scenarios (part XV); the impact of mixing between the radion and the Higgs sector, a fully generic possibility in extra-dimensional models (part XVI); production rates and signatures of universal extra dimensions at hadron colliders (part XVII); black hole production at hadron colliders, which would lead to truly spectacular events (part XVIII). The above contributions represent a tremendous amount of work on the part of the individuals involved and represent the state of the art for many of the currently most important phenomenological research avenues. Of course, much more remains to be done. For example, one should continue to work on assessing the extent to which the discovery reach will be extended if one goes beyond the LHC to the super-high-luminosity LHC (SLHC) or to a very large hadron collider (VLHC) with √s ≈ 40 TeV. Overall, we believe our work shows that the LHC and future hadronic colliders will play a pivotal role in the discovery and study of any kind of new physics beyond the Standard Model. They provide tremendous potential for incredibly exciting new discoveries.


Phenomenological Studies Of Minimal Extensions Of Standard Model

Author by : Nilanjana Kumar
Languange : en
Publisher by : Unknown
Format Available : PDF, ePub, Mobi
Total Read : 53
Total Download : 139
File Size : 55,8 Mb
GET BOOK

Description : The ATLAS and CMS experiments at the Large Hadron Collider (LHC) have confirmed the existence of the Higgs boson, the last missing piece of the Standard Model, making this era a great time to look for beyond Standard Model physics, which can explain the deficiencies in the Standard Model. The research described here is highly motivated by supersymmetry, which appears as an extension of the Standard Model. The phenomenological consequences of that are of great importance and have been reflected in this research. In the first project, the prospects for LHC discovery of a narrow resonance that decays to two Higgs bosons using the bb[macron gammagamma] final state are studied. This study is inspired by the compressed Minimal Supersymmetric Standard Model, which allows the production of stoponium (a bound state of the supersymmetric partners of the top quark and its antiquark) and its decay to Higgs boson pairs, but this study is applicable to any other di-Higgs resonance produced by gluon fusion. The cross-section needed for a 5-sigma discovery at the 14 TeV LHC for such a narrow di-Higgs resonance is estimated as a function of the integrated luminosity, using the invariant mass distributions for bb [macron] and photons. I have also found the integrated luminosity required for discovery of stoponium as a function of its mass. In my second project a viable extension of the Standard Model which incorporates vectorlike fermions near the electroweak scale has been explored. Vectorlike quarks and leptons are exotic new fermions that transform in non-chiral representations of the unbroken Standard Model gauge group. Two models are considered, in which the vectorlike leptons are weak isosinglets and isodoublets. The vectorlike leptons decay to tau leptons. I have studied the prospects for excluding or discovering vectorlike leptons using multilepton events at the LHC. If the vectorlike leptons are weak isosinglets, then discovery in multilepton states is found to be extremely challenging. The prospects for exclusion or discovery of vectorlike leptons at the LHC with existing [radical square root of] s=8 TeV data and future [radical square root] s=13 TeV data are discussed. The study of the effective potential is a very important tool to explore any physics beyond Standard Model because it tells us about vacuum stability and the relation between the Higgs vacuum expectation value and other Lagrangian parameters. In the Standard Model the effective potential gets imaginary contributions when the squared mass of the Goldstone boson is negative, and it suffers from a singularity problem when the squared mass of the Goldstone boson tends to zero. It is possible to resum the SM effective potential to remove those problems associated with Goldstone boson contributions. In my last project I have shown that one can resum the effective potential in MSSM up to two-loop order to negate the spurious contributions from the Goldstone bosons.


Beyond The Standard Model

Author by : Anonim
Languange : en
Publisher by : Unknown
Format Available : PDF, ePub, Mobi
Total Read : 92
Total Download : 208
File Size : 50,7 Mb
GET BOOK

Description : The goal of this proposal was to advance theoretical studies into questions of collider physics at the weak scale, models and signals of dark matter, and connections between neutrino mass and dark energy. The project was a significant success, with a number of developments well beyond what could have been anticipated at the outset. A total of 35 published papers and preprints were produced, with new ideas and signals for LHC physics and dark matter experiments, in particular. A number of new ideas have been found on the possible indirect signals of models of dark matter which relate to the INTEGRAL signal of astrophysical positron production, high energy positrons seen at PAMELA and Fermi, studies into anomalous gamma rays at Fermi, collider signatures of sneutrino dark matter, scenarios of Higgs physics arising in SUSY models, the implications of galaxy cluster surveys for photon-axion conversion models, previously unconsidered collider phenomenology in the form of 'lepton jets' and a very significant result for flavor physics in supersymmetric theories. Progress continues on all fronts, including development of models with dramatic implications for direct dark matter searches, dynamics of dark matter with various excited states, flavor physics, and consequences of modified missing energy signals for collider searches at the LHC.


New Tools In The Search For Supersymmetry

Author by : Michael Jinnxien Saelim
Languange : en
Publisher by : Unknown
Format Available : PDF, ePub, Mobi
Total Read : 79
Total Download : 431
File Size : 53,6 Mb
GET BOOK

Description : The Large Hadron Collider has thrust humanity into the TeV-scale era of particle physics, and with it we have discovered a new Higgs-like particle and set stronger limits on possible theories of supersymmetry and beyond-the-Standard-Model physics. But while the experimental community continues to improve their searches for new physics, the lack of clear beyond-the-Standard-Model discoveries so far has made it apparent that if we are to discover new physics there, the theoretical community must continually develop new methods as well. New tools must be forged and applied to the problems we face at the Large Hadron Collider and possible future particle colliders. This dissertation expresses one contribution, out of many, in this regard. We begin by using boosted top tagging to look for signals of R-parity conserving supersymmetry. Then we use other jet substructure techniques to look for signals of Rparity violating supersymmetry. Lastly, we use the SUSY-Yukawa sum rule to look beyond the phenomenology and probe the crucial cancellation of divergences at the heart of supersymmetric theories.


High Energy Phenomenology Proceedings Of The Workshop

Author by : R Huerta
Languange : en
Publisher by : World Scientific
Format Available : PDF, ePub, Mobi
Total Read : 39
Total Download : 802
File Size : 43,9 Mb
GET BOOK

Description : Contents:Radiative Corrections in the Electroweak Standard Model (M Böhm & A Denner)Hadron Collider Physics (L G Pondrom)Lectures on Heavy Quark Effective Theory (B Grinstein)An Overview of Nonleptonic Decays of B, D, K Mesons and CP-Noninvariance (L-L Chau)Top Quark Physics (G L Kane)High Precision Radiative Corrections in the Semileptonic Decays of Hyperons (S R Juárez W)On the Decay W± → P>±γ (A Queijeiro)The Decay H0→γγ and Physics Beyond the Standard Model (M A Pérez & J J Toscano)Neutrino Masses and Double Beta Decay (J G Hirsch)Neutrino Oscillations in a Medium: Analytic Calculation of Nonadiabatic Transitions (J C D'Olivo)Gauge-Invariant Perturbation Theory Near a Gauge Resonance (R G Stuart)Lower Dimensional Divergences in Gauge Theories (M Vargas & J L L Martínez)Strange Stars: Which is the Ground State of QCD at Finite Baryon Number? (D Page)Experimental Signatures of the SU(5)cc Color Model (O F Hernández)Generalized Supersymmetric Quantum Mechanics (M Moreno & R M Méndez Moreno)Chern-Simons Theories in 2+1 Dimensions (L F Urrutia) Readership: High energy physicists. keywords:


Searches For New Physics At Colliders

Author by : My Phuong Thi Le
Languange : en
Publisher by : Unknown
Format Available : PDF, ePub, Mobi
Total Read : 38
Total Download : 423
File Size : 49,9 Mb
GET BOOK

Description : 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 ($m_{\tilde {g}}$, $m_{\tilde {W}}$, $m_{\tilde {B}}$).