Search for New Phenomena in Three- Or Four-lepton Events in Pp Collisions at [square Root]s

Search for New Phenomena in Three- Or Four-lepton Events in Pp Collisions at [square Root]s

Author: [Study Group] ATLAS Collaboration CERN

Publisher:

Published: 2022

Total Pages: 0

ISBN-13:

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Abstract: A search with minimal model dependence for physics beyond the Standard Model in events featuring three or four charged leptons (3l and 4l, ) is presented. The analysis aims to be sensitive to a wide range of potential new-physics theories simultaneously. This analysis uses data from pp collisions delivered by the Large Hadron Collider at a centre-of-mass energy of TeV and recorded with the ATLAS detector, corresponding to the full Run 2 dataset of 139 fb−1. The 3l and 4l phase space is divided into 22 event categories according to the number of leptons in the event, the missing transverse momentum, the invariant mass of the leptons, and the presence of leptons originating from a Z-boson candidate. These event categories are analysed independently for the presence of deviations from the Standard Model. No statistically significant deviations from the Standard Model predictions are observed. Upper limits for all signal regions are reported in terms of the visible cross-section


Search for Anomalous Production of Events with Three Or More Leptons in Pp Collisions at Sqrt(s)

Search for Anomalous Production of Events with Three Or More Leptons in Pp Collisions at Sqrt(s)

Author:

Publisher:

Published: 2014

Total Pages: 27

ISBN-13:

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A search for physics beyond the standard model in events with at least three leptons is presented. The data sample, corresponding to an integrated luminosity of 19.5 inverse femtobarns of proton-proton collisions with center-of-mass energy sqrt(s) = 8 TeV, was collected by the CMS experiment at the LHC during 2012. The data are divided into exclusive categories based on the number of leptons and their flavor, the presence or absence of an opposite-sign, same-flavor lepton pair (OSSF), the invariant mass of the OSSF pair, the presence or absence of a tagged bottom-quark jet, the number of identified hadronically decaying tau leptons, and the magnitude of the missing transverse energy and of the scalar sum of jet transverse momenta. The numbers of observed events are found to be consistent with the expected numbers from standard model processes, and limits are placed on new-physics scenarios that yield multilepton final states. In particular, scenarios that predict Higgs boson production in the context of supersymmetric decay chains are examined. We also place a 95% confidence level upper limit of 1.3% on the branching fraction for the decay of a top quark to a charm quark and a Higgs boson (t to c H), which translates to a bound on the left- and right-handed top-charm flavor-violating Higgs Yukawa couplings, lambda[H, tc] and lambda[H, ct], respectively, of sqrt(abs(lambda[H, tc])2̂ + abs(lambda[H, ct])2̂)


Supersymmetry and String Theory

Supersymmetry and String Theory

Author: Michael Dine

Publisher: Cambridge University Press

Published: 2007-01-04

Total Pages: 481

ISBN-13: 113946244X

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The past decade has witnessed dramatic developments in the field of theoretical physics. This book is a comprehensive introduction to these recent developments. It contains a review of the Standard Model, covering non-perturbative topics, and a discussion of grand unified theories and magnetic monopoles. It introduces the basics of supersymmetry and its phenomenology, and includes dynamics, dynamical supersymmetry breaking, and electric-magnetic duality. The book then covers general relativity and the big bang theory, and the basic issues in inflationary cosmologies before discussing the spectra of known string theories and the features of their interactions. The book also includes brief introductions to technicolor, large extra dimensions, and the Randall-Sundrum theory of warped spaces. This will be of great interest to graduates and researchers in the fields of particle theory, string theory, astrophysics and cosmology. The book contains several problems, and password protected solutions will be available to lecturers at www.cambridge.org/9780521858410.


Mass and Motion in General Relativity

Mass and Motion in General Relativity

Author: Luc Blanchet

Publisher: Springer Science & Business Media

Published: 2011-01-19

Total Pages: 634

ISBN-13: 9048130158

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From the infinitesimal scale of particle physics to the cosmic scale of the universe, research is concerned with the nature of mass. While there have been spectacular advances in physics during the past century, mass still remains a mysterious entity at the forefront of current research. Our current perspective on gravitation has arisen over millennia, through the contemplation of falling apples, lift thought experiments and notions of stars spiraling into black holes. In this volume, the world’s leading scientists offer a multifaceted approach to mass by giving a concise and introductory presentation based on insights from their respective fields of research on gravity. The main theme is mass and its motion within general relativity and other theories of gravity, particularly for compact bodies. Within this framework, all articles are tied together coherently, covering post-Newtonian and related methods as well as the self-force approach to the analysis of motion in curved space-time, closing with an overview of the historical development and a snapshot on the actual state of the art. All contributions reflect the fundamental role of mass in physics, from issues related to Newton’s laws, to the effect of self-force and radiation reaction within theories of gravitation, to the role of the Higgs boson in modern physics. High-precision measurements are described in detail, modified theories of gravity reproducing experimental data are investigated as alternatives to dark matter, and the fundamental problem of reconciling any theory of gravity with the physics of quantum fields is addressed. Auxiliary chapters set the framework for theoretical contributions within the broader context of experimental physics. The book is based upon the lectures of the CNRS School on Mass held in Orléans, France, in June 2008. All contributions have been anonymously refereed and, with the cooperation of the authors, revised by the editors to ensure overall consistency.


Resistive Gaseous Detectors

Resistive Gaseous Detectors

Author: Marcello Abbrescia

Publisher: John Wiley & Sons

Published: 2018-06-11

Total Pages: 404

ISBN-13: 3527340769

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This first book to critically summarize the latest achievements and emerging applications within this interdisciplinary topic focuses on one of the most important types of detectors for elementary particles and photons: resistive plate chambers (RPCs). In the first part, the outstanding, international team of authors comprehensively describes and presents the features and design of single and double-layer RPCs before covering more advanced multi-layer RPCs. The second part then focuses on the application of RPCs in high energy physics, materials science, medicine and security. Throughout, the experienced authors adopt a didactic approach, with each subject presented in a simple way, increasing in complexity step by step.


Dictionary of Geophysics, Astrophysics, and Astronomy

Dictionary of Geophysics, Astrophysics, and Astronomy

Author: Richard A. Matzner

Publisher: CRC Press

Published: 2018-10-08

Total Pages: 536

ISBN-13: 1420050230

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The Dictionary of Geophysics, Astrophysics, and Astronomy provides a lexicon of terminology covering fields such as astronomy, astrophysics, cosmology, relativity, geophysics, meteorology, Newtonian physics, and oceanography. Authors and editors often assume - incorrectly - that readers are familiar with all the terms in professional literature. With over 4,000 definitions and 50 contributing authors, this unique comprehensive dictionary helps scientists to use terminology correctly and to understand papers, articles, and books in which physics-related terms appear.


On Three Levels

On Three Levels

Author: Mark Fannes

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 467

ISBN-13: 1461524601

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This volume contains the proceedings of a five-day NATO Advanced Research Workshop "On Three Levels, the mathematical physics of micro-, meso-, and macro phenomena," conducted from July 19 to 23 in Leuven, Belgium. The main purpose of the workshop was to bring together and to confront where relevant, classical and quantum approaches in the rigorous study of the relation between the various levels of physical description. The reader will find here discussions on a variety of topics involving a broad range of scales. For the micro-level, contributions are presented on models of reaction-diffusion pro cesses, quantum groups and quantum spin systems. The reports on quantum disorder, the quantum Hall effect, semi-classical approaches of wave mechanics and the random Schrodinger equation can be situated on the meso-level. Discussions on macroscopic quantum effects and large scale fluctuations are dealing with the macroscopic level of description. These three levels are however not independent and emphasis is put on relating these scales of description. This is especially the case for the contributions on kinetic and hydrodynamicallimits, the discussions on large deviations and the strong and weak coupling limits. The advisory board was composed of J.L. Lebowitz, J.T. Lewis and E.H. Lieb. The organizing committee was formed by Ph.A. Martin, G.L. Sewell, E.R. Speer and A.


Introduction to Particle Cosmology

Introduction to Particle Cosmology

Author: Cosimo Bambi

Publisher: Springer

Published: 2015-08-14

Total Pages: 251

ISBN-13: 3662480786

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This book introduces the basic concepts of particle cosmology and covers all the main aspects of the Big Bang Model (expansion of the Universe, Big Bang Nucleosynthesis, Cosmic Microwave Background, large scale structures) and the search for new physics (inflation, baryogenesis, dark matter, dark energy). It also includes the majority of recent discoveries, such as the precise determination of cosmological parameters using experiments like WMAP and Planck, the discovery of the Higgs boson at LHC, the non-discovery to date of supersymmetric particles, and the search for the imprint of gravitational waves on the CMB polarization by Planck and BICEP. This textbook is based on the authors’ courses on Cosmology, and aims at introducing Particle Cosmology to senior undergraduate and graduate students. It has been especially written to be accessible even for those students who do not have a strong background in General Relativity and quantum field theory. The content of this book is organized in an easy-to-use style and students will find it a helpful research guide.


Frontiers of Fundamental Physics 4

Frontiers of Fundamental Physics 4

Author: B. G. Sidharth

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 350

ISBN-13: 1461513391

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This symposium was organized at the B.M. Birla Science Centre, Hyderabad, India, and provided a platform for frontier physicists to exchange ideas and review the latest work and developments on a variety of interrelated topics. A feature of the symposium, as well as the proceedings, is the B.M. Birla Memorial Lecture by Nobel Laureate Professor Gerard 't Hooft. There were participants from the USA, several European countries, Russia and CIS countries, South Africa, Japan, India and elsewhere, of whom some forty scientists presented papers. Spanning a wide range of contemporary issues in fundamental physics from string theory to cosmology, the proceedings present many of these talks and contributions.