Search for Charginos Nearly Mass-Degenerate with the Lightest Neutralino

Search for Charginos Nearly Mass-Degenerate with the Lightest Neutralino PDF Author: Shingo Kazama
Publisher: Springer
ISBN: 4431556575
Category : Science
Languages : en
Pages : 155

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Book Description
In this book, the anomaly mediated supersymmetry breaking (AMSB) model is explored by searching for charged winos with their subsequent decays collected with the ATLAS detector at the Large Hadron Collider (LHC). The author develops a new method, called “re-tracking,” to detect charged winos that decay before reaching the Semiconductor Tracker (SCT) detector. Because the nominal tracking algorithm at the ATLAS experiment requires at least seven successive hits in the inner tracking system, the sensitivity to charged winos having a fraction of a nanosecond in the past analysis was therefore limited. However, re-tracking requires a minimum of three pixel hits and provides a fully efficient tracking capability for charged winos traversing the pixel detector, resulting in around about 100 times greater efficiency for charged winos with a lifetime ~0.2 ns longer than that in past searches. Signal topology is characterized by a jet with large transverse momentum (pT), large missing transverse energy, and a high-pT disappearing track. There are three types of back ground tracks: interacting hadron tracks, charged leptons, and tracks with mismeasured pT. A background estimation based on the Monte Carlo (MC) simulation suffers from large uncertainties due to poor statistics and has difficulty simulating the properties of background tracks. Therefore, a data-driven approach has been developed by the author of the book to estimate the background track-pT spectrum. No significant excess above the background expectation is observed for candidate tracks with large transverse momentum, and constraints on the AMSB model are obtained. The author shows that in the AMSB model, a charged wino mass below 270 GeV is excluded at 95 % confidence level, which also directly constrains the mass of wino dark matter.

Search for Charginos Nearly Mass-Degenerate with the Lightest Neutralino

Search for Charginos Nearly Mass-Degenerate with the Lightest Neutralino PDF Author: Shingo Kazama
Publisher: Springer
ISBN: 4431556575
Category : Science
Languages : en
Pages : 155

Get Book Here

Book Description
In this book, the anomaly mediated supersymmetry breaking (AMSB) model is explored by searching for charged winos with their subsequent decays collected with the ATLAS detector at the Large Hadron Collider (LHC). The author develops a new method, called “re-tracking,” to detect charged winos that decay before reaching the Semiconductor Tracker (SCT) detector. Because the nominal tracking algorithm at the ATLAS experiment requires at least seven successive hits in the inner tracking system, the sensitivity to charged winos having a fraction of a nanosecond in the past analysis was therefore limited. However, re-tracking requires a minimum of three pixel hits and provides a fully efficient tracking capability for charged winos traversing the pixel detector, resulting in around about 100 times greater efficiency for charged winos with a lifetime ~0.2 ns longer than that in past searches. Signal topology is characterized by a jet with large transverse momentum (pT), large missing transverse energy, and a high-pT disappearing track. There are three types of back ground tracks: interacting hadron tracks, charged leptons, and tracks with mismeasured pT. A background estimation based on the Monte Carlo (MC) simulation suffers from large uncertainties due to poor statistics and has difficulty simulating the properties of background tracks. Therefore, a data-driven approach has been developed by the author of the book to estimate the background track-pT spectrum. No significant excess above the background expectation is observed for candidate tracks with large transverse momentum, and constraints on the AMSB model are obtained. The author shows that in the AMSB model, a charged wino mass below 270 GeV is excluded at 95 % confidence level, which also directly constrains the mass of wino dark matter.

Fundamental Interactions

Fundamental Interactions PDF Author: A. Astbury
Publisher: World Scientific
ISBN: 9789810249120
Category : Science
Languages : en
Pages : 408

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Book Description
The Lake Louise Winter Institute is held annually to explore recent trends in physics. The proceedings contain pedagogical and review lectures by invited experts and contributed presentations by participants.

Fundamental Interactions - Proceedings Of The Sixteenth Lake Louise Winter Institute

Fundamental Interactions - Proceedings Of The Sixteenth Lake Louise Winter Institute PDF Author: Alan Astbury
Publisher: World Scientific
ISBN: 9814488852
Category : Science
Languages : en
Pages : 405

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Book Description
The Lake Louise Winter Institute is held annually to explore recent trends in physics. The proceedings contain pedagogical and review lectures by invited experts and contributed presentations by participants.

Beyond the Desert 2002

Beyond the Desert 2002 PDF Author: H. V. Klapdor-Kleingrothaus
Publisher: CRC Press
ISBN: 148228958X
Category : Science
Languages : en
Pages : 763

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Book Description
Containing the Proceedings of the Third International Conference on Physics Beyond the Standard Model, this book reports the latest experimental and theoretical results and ideas in this exciting field, at the interface between particle physics, astrophysics, and nuclear physics. Taken as a whole, this book presents an overview of the current statu

Particles, Strings And Cosmology (Pascos 99), Procs Of 7th Intl Symp

Particles, Strings And Cosmology (Pascos 99), Procs Of 7th Intl Symp PDF Author: Kingman Cheung
Publisher: World Scientific
ISBN: 9814492574
Category : Science
Languages : en
Pages : 588

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Book Description
The PASCOS (International Symposium on Particles, Strings and Cosmology) series brings together the leading experts and most active young researchers in the closely related fields of elementary particle physics, string theory and cosmology/astrophysics. These areas of research have become increasingly intertwined in recent years, each having direct impact on the others. In particular, there has been a dramatic expansion of ideas from particle theory and string theory that have vast impact on cosmology, especially our picture of the early universe and its evolution. Correspondingly, the proliferation of data regarding the early universe, and its increasing precision, has begun to strongly constrain the theoretical models. Meanwhile, observations of neutrino oscillations and cosmic ray excesses, and limits on new physics from colliders and other particle experiments, as well as the resulting restrictions on theoretical and phenomenological modeling, are becoming ever stronger. During PASCOS99, it became clear that the long-awaited era of convergence of these fields is truly at hand.The proceedings of PASCOS 99 reflect the accelerating overlap and convergence of the fields of elementary particles physics, string theory and cosmology/astrophysics. Plenary reviews by leading figures in these fields provide perspectives on these interrelationships and up-to-the-minute summaries of recent progress in the various areas. Parallel talk summaries focus on many of the topics within each field of greatest current interest and activity. Both the plenary and parallel writeups are designed to be descriptive in nature and avoid being overly technical. As a result, the volume can serve as a useful reference for students and professionals in all three fields. Careful referencing allows further pursuit of a given topic. Overall, the proceedings are unique in that they not only bring together in a single volume comprehensive overview of the great progress being made in all three of these very exciting fields, but also provide a snapshot of how particles, strings and cosmology are increasingly impacting one another.

Proceedings of the 7th International Symposium Particles, Strings and Cosmology

Proceedings of the 7th International Symposium Particles, Strings and Cosmology PDF Author: Kingman Cheung
Publisher: World Scientific
ISBN: 9789810243883
Category : Science
Languages : en
Pages : 588

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Book Description
The PASCOS (International Symposium on Particles, Strings and Cosmology) series brings together the leading experts and most active young researchers in the closely related fields of elementary particle physics, string theory and cosmology/astrophysics. These areas of research have become increasingly intertwined in recent years, each having direct impact on the others. In particular, there has been a dramatic expansion of ideas from particle theory and string theory that have vast impact on cosmology, especially our picture of the early universe and its evolution. Correspondingly, the proliferation of data regarding the early universe, and its increasing precision, has begun to strongly constrain the theoretical models. Meanwhile, observations of neutrino oscillations and cosmic ray excesses, and limits on new physics from colliders and other particle experiments, as well as the resulting restrictions on theoretical and phenomenological modeling, are becoming ever stronger. During PASCOS99, it became clear that the long-awaited era of convergence of these fields is truly at hand.The proceedings of PASCOS 99 reflect the accelerating overlap and convergence of the fields of elementary particles physics, string theory and cosmology/astrophysics. Plenary reviews by leading figures in these fields provide perspectives on these interrelationships and up-to-the-minute summaries of recent progress in the various areas. Parallel talk summaries focus on many of the topics within each field of greatest current interest and activity. Both the plenary and parallel writeups are designed to be descriptive in nature and avoid being overly technical. As a result, the volume can serve as a useful reference for students and professionals in all three fields. Careful referencing allows further pursuit of a given topic. Overall, the proceedings are unique in that they not only bring together in a single volume comprehensive overview of the great progress being made in all three of these very exciting fields, but also provide a snapshot of how particles, strings and cosmology are increasingly impacting one another.

The Physics Associated with Neutrino Masses

The Physics Associated with Neutrino Masses PDF Author: Diego Aristizabal Sierra
Publisher: Frontiers Media SA
ISBN: 2889633519
Category :
Languages : en
Pages : 293

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Book Description
This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.

XX International Symposium on Lepton and Photon Interactions at High Energies

XX International Symposium on Lepton and Photon Interactions at High Energies PDF Author: Juliet Lee-Franzini
Publisher: World Scientific
ISBN: 9789810248802
Category : Science
Languages : en
Pages : 672

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Book Description
This important book covers topics that are of major interest to the high energy physics community, including the most recent results from flavour factories, dark matter and neutrino physics. In addition, it considers future high energy machines.

Particles And Fields - Proceedings Of The X Jorge Andre Swieca Summer School

Particles And Fields - Proceedings Of The X Jorge Andre Swieca Summer School PDF Author: Joao Carlos Alves Barata
Publisher: World Scientific
ISBN: 9814543012
Category : Science
Languages : en
Pages : 518

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Book Description
This book constitutes the proceedings of the X Jorge André Swieca Summer School — Particles and Fields. It includes topics on non-commutative geometry, constructive quantum field theory and duality in quantum field theory, as well as various subjects in high energy physics and phenomenology.

Atlas: A 25-year Insider Story Of The Lhc Experiment

Atlas: A 25-year Insider Story Of The Lhc Experiment PDF Author: Peter Jenni
Publisher: World Scientific
ISBN: 9813271817
Category : Science
Languages : en
Pages : 372

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Book Description
This book is written by the ATLAS Collaboration at CERN's Large Hadron Collider (LHC), to document and reflect on its more than 25 years of history. It covers all aspects of this global science project at the forefront of particle physics. The historical part recalls first the early stages of discussions in the community leading to the formation of the collaboration in 1992. In a unique approach, the second part documents the evolution from early detector concepts to the final instrument, covering the technical, financial and human aspects. This includes the phases of construction of detector components in the various institutes around the world as well as their installation and commissioning in the underground cavern at CERN.An important part is devoted to the operation of the whole experiment. The book highlights the capabilities and physics accomplishments so far, including the Higgs boson discovery (jointly announced with CMS). It features the various aspects of a broad spectrum of activities needed to arrive at the physics results. The book includes also an outlook to the detector upgrade activities preparing the experiment for the high-luminosity LHC phase of the next decades. Last but not least, it reveals the human aspects of the large ATLAS community working together pursuing common physics goals.The book is aimed at a broad readership with interest in large science projects and their history, as well as in the human endeavour of a worldwide collaboration.