Heavy Neutral Particle Decays to Tau Pairs

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Publisher : Springer Science & Business Media
ISBN 13 : 3319032577
Total Pages : 161 pages
Book Rating : 4.3/5 (19 download)

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Book Synopsis Heavy Neutral Particle Decays to Tau Pairs by : Michail Bachtis

Download or read book Heavy Neutral Particle Decays to Tau Pairs written by Michail Bachtis and published by Springer Science & Business Media. This book was released on 2013-12-13 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work presented in this thesis spans a wide range of experimental particle physics subjects, starting from level-1 trigger electronics to the final results of the search for Higgs boson decay and to tau lepton pairs. The thesis describes an innovative reconstruction algorithm for tau decays and details how it was instrumental in providing a measurement of Z decay to tau lepton pairs. The reliability of the analysis is fully established by this measurement before the Higgs boson decay to tau lepton pairs is considered. The work described here continues to serve as a model for analysing CMS Higgs to tau leptons measurements.

Report of Research Activities

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Publisher :
ISBN 13 :
Total Pages : 80 pages
Book Rating : 4.3/5 ( download)

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Book Synopsis Report of Research Activities by : Yale University. Cowles Foundation for Research in Economics

Download or read book Report of Research Activities written by Yale University. Cowles Foundation for Research in Economics and published by . This book was released on 1959 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Search for Higgs Boson Pair Production in the bb̅ τ+ τ- Decay Channel

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Publisher : Springer
ISBN 13 : 3030040550
Total Pages : 283 pages
Book Rating : 4.0/5 (3 download)

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Book Synopsis Search for Higgs Boson Pair Production in the bb̅ τ+ τ- Decay Channel by : Luca Cadamuro

Download or read book Search for Higgs Boson Pair Production in the bb̅ τ+ τ- Decay Channel written by Luca Cadamuro and published by Springer. This book was released on 2018-12-06 with total page 283 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents innovative contributions to the CMS experiment in the new trigger system for the restart of the LHC collisions in Run II, as well as original analysis methods and important results that led to official publications of the Collaboration. The author's novel reconstruction algorithms, deployed on the Field-Programmable Gate Arrays of the new CMS trigger architecture, have brought a gain of over a factor 2 in efficiency for the identification of tau leptons, with a very significant impact on important H boson measurements, such as its decays to tau lepton pairs and the search for H boson pair production. He also describes a novel analysis of HH → bb tautau, a high priority physics topic in a difficult channel. The original strategy, optimisation of event categories, and the control of the background have made the result one of the most sensitive concerning the self-coupling of the Higgs boson among all possible channels at the LHC.

String Theory For Dummies

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Publisher : John Wiley & Sons
ISBN 13 : 047046724X
Total Pages : 387 pages
Book Rating : 4.4/5 (74 download)

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Book Synopsis String Theory For Dummies by : Andrew Zimmerman Jones

Download or read book String Theory For Dummies written by Andrew Zimmerman Jones and published by John Wiley & Sons. This book was released on 2009-11-16 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: A clear, plain-English guide to this complex scientific theory String theory is the hottest topic in physics right now, with books on the subject (pro and con) flying out of the stores. String Theory For Dummies offers an accessible introduction to this highly mathematical "theory of everything," which posits ten or more dimensions in an attempt to explain the basic nature of matter and energy. Written for both students and people interested in science, this guide explains concepts, discusses the string theory's hypotheses and predictions, and presents the math in an approachable manner. It features in-depth examples and an easy-to-understand style so that readers can understand this controversial, cutting-edge theory.

Search for the Higgs Boson Produced in Association with Top Quarks with the CMS Detector at the LHC

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Publisher : Springer Nature
ISBN 13 : 3030902064
Total Pages : 291 pages
Book Rating : 4.0/5 (39 download)

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Book Synopsis Search for the Higgs Boson Produced in Association with Top Quarks with the CMS Detector at the LHC by : Cristina Martin Perez

Download or read book Search for the Higgs Boson Produced in Association with Top Quarks with the CMS Detector at the LHC written by Cristina Martin Perez and published by Springer Nature. This book was released on 2022-02-09 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, the interaction between the Higgs boson and the top quark is studied with the proton-proton collisions at 13 TeV provided by the LHC at the CMS detector at CERN (Geneva). At the LHC, these particles are produced simultaneously via the associate production of the Higgs boson with one top quark (tH process) or two top quarks (ttH process). Compared to many other possible outcomes of the proton-proton interactions, these processes are very rare, as the top quark and the Higgs boson are the heaviest elementary particles known. Hence, identifying them constitutes a significant experimental challenge. A high particle selection efficiency in the CMS detector is therefore crucial. At the core of this selection stands the Level-1 (L1) trigger system, a system that filters collision events to retain only those with potential interest for physics analysis. The selection of hadronically decaying τ leptons, expected from the Higgs boson decays, is especially demanding due to the large background arising from the QCD interactions. The first part of this thesis presents the optimization of the L1 τ algorithm in Run 2 (2016-2018) and Run 3 (2022-2024) of the LHC. It includes the development of a novel trigger concept for the High-Luminosity LHC, foreseen to start in 2027 and to deliver 5 times the current instantaneous luminosity. To this end, sophisticated algorithms based on machine learning approaches are used, facilitated by the increasingly modern technology and powerful computation of the trigger system. The second part of the work presents the search of the tH and ttH processes with the subsequent decays of the Higgs boson to pairs of τ lepton, W bosons or Z bosons, making use of the data recorded during Run 2. The presence of multiple particles in the final state, along with the low cross section of the processes, makes the search an ideal use case for multivariant discriminants that enhance the selectivity of the signals and reject the overwhelming background contributions. The discriminants presented are built using state-of-the-art machine learning techniques, able to capture the correlations amongst the processes involved, as well as the so-called Matrix Element Method (MEM), which combines the theoretical description of the processes with the detector resolution effects. The level of sophistication of the methods used, along with the unprecedented amount of collision data analyzed, result in the most stringent measurements of the tH and ttH cross sections up to date.

Search for the Higgs Boson in the Vector Boson Fusion Channel at the ATLAS Detector

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Publisher : Springer
ISBN 13 : 3319135996
Total Pages : 114 pages
Book Rating : 4.3/5 (191 download)

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Book Synopsis Search for the Higgs Boson in the Vector Boson Fusion Channel at the ATLAS Detector by : Eric Ouellette

Download or read book Search for the Higgs Boson in the Vector Boson Fusion Channel at the ATLAS Detector written by Eric Ouellette and published by Springer. This book was released on 2015-01-20 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Thesis describes the first measurement of, and constraints on, Higgs boson production in the vector boson fusion mode, where the Higgs decays to b quarks (the most common decay channel), at the LHC. The vector boson fusion mode, in which the Higgs is produced simultaneously with a pair of quark jets, provides an unparalleled opportunity to study the detailed properties of the Higgs, including the possibility of parity and CP violation, as well as its couplings and mass. It thus opens up this new field of study for precision investigation as the LHC increases in energy and intensity, leading the way to this new and exciting arena of precision Higgs research.

LHC Physics

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Publisher : CRC Press
ISBN 13 : 1439837708
Total Pages : 415 pages
Book Rating : 4.4/5 (398 download)

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Book Synopsis LHC Physics by : T. Binoth

Download or read book LHC Physics written by T. Binoth and published by CRC Press. This book was released on 2012-04-25 with total page 415 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exploring the phenomenology of the Large Hadron Collider (LHC) at CERN, LHC Physics focuses on the first years of data collected at the LHC as well as the experimental and theoretical tools involved. It discusses a broad spectrum of experimental and theoretical activity in particle physics, from the searches for the Higgs boson and physics beyond the Standard Model to studies of quantum chromodynamics, the B-physics sector, and the properties of dense hadronic matter in heavy-ion collisions. Covering the topics in a pedagogical manner, the book introduces the theoretical and phenomenological framework of hadron collisions and presents the current theoretical models of frontier physics. It offers overviews of the main detector components, the initial calibration procedures, and search strategies. The authors also provide explicit examples of physics analyses drawn from the recently shut down Tevatron. In the coming years, or perhaps even sooner, the LHC experiments may reveal the Higgs boson and offer insight beyond the Standard Model. Written by some of the most prominent and active researchers in particle physics, this volume equips new physicists with the theory and tools needed to understand the various LHC experiments and prepares them to make future contributions to the field.

Polarization at LEP

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Publisher :
ISBN 13 :
Total Pages : 364 pages
Book Rating : 4.:/5 ( download)

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Book Synopsis Polarization at LEP by :

Download or read book Polarization at LEP written by and published by . This book was released on 1988 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Scalar Boson Decays to Tau Leptons

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Publisher : Springer
ISBN 13 : 3319706500
Total Pages : 282 pages
Book Rating : 4.3/5 (197 download)

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Book Synopsis Scalar Boson Decays to Tau Leptons by : Cécile Caillol

Download or read book Scalar Boson Decays to Tau Leptons written by Cécile Caillol and published by Springer. This book was released on 2017-11-15 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a study of the scalar sector in the standard model (SM), as well as various searches for an extended scalar sector in theories beyond the SM (BSM). The first part of the thesis details the search for an SM Higgs boson decaying to taus, and produced by gluon fusion, vector boson fusion, or associated production with a vector boson, leading to evidence for decays of the Higgs boson to taus. In turn, the second part highlights several searches for an extended scalar sector, with scalar boson decays to taus. In all of the analyses presented, at least one scalar boson decays to a pair of taus. The results draw on data collected by the Compact Muon Solenoid (CMS) detector during proton–proton collisions with a center-of-mass energy of 7 or 8 TeV.

Lie Theory and Its Applications in Physics

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Publisher : Springer Nature
ISBN 13 : 9811577757
Total Pages : 552 pages
Book Rating : 4.8/5 (115 download)

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Book Synopsis Lie Theory and Its Applications in Physics by : Vladimir Dobrev

Download or read book Lie Theory and Its Applications in Physics written by Vladimir Dobrev and published by Springer Nature. This book was released on 2020-10-15 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents modern trends in the area of symmetries and their applications based on contributions to the workshop "Lie Theory and Its Applications in Physics" held near Varna (Bulgaria) in June 2019. Traditionally, Lie theory is a tool to build mathematical models for physical systems. Recently, the trend is towards geometrization of the mathematical description of physical systems and objects. A geometric approach to a system yields in general some notion of symmetry, which is very helpful in understanding its structure. Geometrization and symmetries are meant in their widest sense, i.e., representation theory, algebraic geometry, number theory, infinite-dimensional Lie algebras and groups, superalgebras and supergroups, groups and quantum groups, noncommutative geometry, symmetries of linear and nonlinear partial differential operators, special functions, and others. Furthermore, the necessary tools from functional analysis are included. This is a large interdisciplinary and interrelated field. The topics covered in this volume from the workshop represent the most modern trends in the field : Representation Theory, Symmetries in String Theories, Symmetries in Gravity Theories, Supergravity, Conformal Field Theory, Integrable Systems, Polylogarithms, and Supersymmetry. They also include Supersymmetric Calogero-type models, Quantum Groups, Deformations, Quantum Computing and Deep Learning, Entanglement, Applications to Quantum Theory, and Exceptional Quantum Algebra for the standard model of particle physics This book is suitable for a broad audience of mathematicians, mathematical physicists, and theoretical physicists, including researchers and graduate students interested in Lie Theory.

A Beauty-ful Boson

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Publisher : Springer Nature
ISBN 13 : 3031200136
Total Pages : 229 pages
Book Rating : 4.0/5 (312 download)

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Book Synopsis A Beauty-ful Boson by : Giulia Di Gregorio

Download or read book A Beauty-ful Boson written by Giulia Di Gregorio and published by Springer Nature. This book was released on 2023-01-01 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: The analysis described in this thesis is the search for the Higgs boson, decaying into bb pair, in the associated production with a vector boson, in the extreme Higgs boson transverse momentum region where the Higgs boson is reconstructed using the large-R jet technique. The use of the large-R jets allows to add a part of the phase space unexplored so far, which is particularly sensitive to possible new physics. The analysed data have been collected at LHC by the ATLAS detector between 2015 and 2018 at a centre-of-mass energy of √s = 13 TeV. The same dataset has been used to perform the differential pp → ZH and pp → WH cross-section measurements used to extract the information on the Higgs couplings and to put limits on Beyond the Standard Model effects. Furthermore the analysis has been re-used to perform a cross-section measurement of the diboson ZZ and WZ processes because the diboson and the Higgs processes have a similar topology. For the first time the ZZ(bb) and WZ(bb) cross-sections are measured at √s = 13 TeV and the observed cross-section measurements are consistent with the Standard Model predictions.

X-Ray Lasers 2018

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Publisher : Springer Nature
ISBN 13 : 3030354539
Total Pages : 207 pages
Book Rating : 4.0/5 (33 download)

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Book Synopsis X-Ray Lasers 2018 by : Michaela Kozlová

Download or read book X-Ray Lasers 2018 written by Michaela Kozlová and published by Springer Nature. This book was released on 2020-03-06 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings gather a selection of invited and contributed papers presented during the 16th International Conference on X-Ray Lasers (ICXRL 2018), held in Prague, Czech Republic, from 7 to 12 October 2018. The conference is part of an ongoing series dedicated to recent developments in the science and technology of X-ray lasers and other coherent X-ray sources, with an additional focus on supporting technologies, instrumentation and applications. The book highlights advances in a wide range of fields including laser and discharge-pumped plasma X-ray lasers, the injection and seeding of X-ray amplifiers, high-order harmonic generation and ultrafast phenomena, X-ray free electron lasers, novel schemes for (in)coherent XUV, X-ray and γ-ray generation, XUV and X-ray imaging, optics and metrology, X-rays and γ-rays for fundamental science, the practical implementation of X-ray lasers, XFELs and super-intense lasers, and the applications and industrial uses of X-ray lasers.

Search for tt̄H Production in the H → bb̅ Decay Channel

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Publisher : Springer Nature
ISBN 13 : 3030653803
Total Pages : 217 pages
Book Rating : 4.0/5 (36 download)

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Book Synopsis Search for tt̄H Production in the H → bb̅ Decay Channel by : Marcel Rieger

Download or read book Search for tt̄H Production in the H → bb̅ Decay Channel written by Marcel Rieger and published by Springer Nature. This book was released on 2021-02-25 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 1964, a mechanism explaining the origin of particle masses was proposed by Robert Brout, François Englert, and Peter W. Higgs. 48 years later, in 2012, the so-called Higgs boson was discovered in proton-proton collisions recorded by experiments at the LHC. Since then, its ability to interact with quarks remained experimentally unconfirmed. This book presents a search for Higgs bosons produced in association with top quarks tt̄H in data recorded with the CMS detector in 2016. It focuses on Higgs boson decays into bottom quarks H → bb̅ and top quark pair decays involving at least one lepton. In this analysis, a multiclass classification approach using deep learning techniques was applied for the first time. In light of the dominant background contribution from tt̄ production, the developed method proved to achieve superior sensitivity with respect to existing techniques. In combination with searches in different decay channels, the presented work contributed to the first observations of tt̄H production and H → bb̅ decays.

Search for Charged Higgs Bosons Decaying Into Top and Bottom Quarks with Single-lepton Final States Using Pp Collisions Collected at a Centre-of-mass Energy of 13 TeV by the ATLAS Detector

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (11 download)

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Book Synopsis Search for Charged Higgs Bosons Decaying Into Top and Bottom Quarks with Single-lepton Final States Using Pp Collisions Collected at a Centre-of-mass Energy of 13 TeV by the ATLAS Detector by : Francesco Peri

Download or read book Search for Charged Higgs Bosons Decaying Into Top and Bottom Quarks with Single-lepton Final States Using Pp Collisions Collected at a Centre-of-mass Energy of 13 TeV by the ATLAS Detector written by Francesco Peri and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Higgs Boson Decays into a Pair of Bottom Quarks

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Publisher : Springer Nature
ISBN 13 : 3030879380
Total Pages : 171 pages
Book Rating : 4.0/5 (38 download)

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Book Synopsis Higgs Boson Decays into a Pair of Bottom Quarks by : Cecilia Tosciri

Download or read book Higgs Boson Decays into a Pair of Bottom Quarks written by Cecilia Tosciri and published by Springer Nature. This book was released on 2021-10-22 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: The discovery in 2012 of the Higgs boson at the Large Hadron Collider (LHC) represents a milestone for the Standard Model (SM) of particle physics. Most of the SM Higgs production and decay rates have been measured at the LHC with increased precision. However, despite its experimental success, the SM is known to be only an effective manifestation of a more fundamental description of nature. The scientific research at the LHC is strongly focused on extending the SM by searching, directly or indirectly, for indications of New Physics. The extensive physics program requires increasingly advanced computational and algorithmic techniques. In the last decades, Machine Learning (ML) methods have made a prominent appearance in the field of particle physics, and promise to address many challenges faced by the LHC. This thesis presents the analysis that led to the observation of the SM Higgs boson decay into pairs of bottom quarks. The analysis exploits the production of a Higgs boson associated with a vector boson whose signatures enable efficient triggering and powerful background reduction. The main strategy to maximise the signal sensitivity is based on a multivariate approach. The analysis is performed on a dataset corresponding to a luminosity of 79.8/fb collected by the ATLAS experiment during Run-2 at a centre-of-mass energy of 13 TeV. An excess of events over the expected background is found with an observed (expected) significance of 4.9 (4.3) standard deviation. A combination with results from other \Hbb searches provides an observed (expected) significance of 5.4 (5.5). The corresponding ratio between the signal yield and the SM expectation is 1.01 +- 0.12 (stat.)+ 0.16-0.15(syst.). The 'observation' analysis was further extended to provide a finer interpretation of the V H(H → bb) signal measurement. The cross sections for the VH production times the H → bb branching ratio have been measured in exclusive regions of phase space. These measurements are used to search for possible deviations from the SM with an effective field theory approach, based on anomalous couplings of the Higgs boson. The results of the cross-section measurements, as well as the constraining of the operators that affect the couplings of the Higgs boson to the vector boson and the bottom quarks, have been documented and discussed in this thesis. This thesis also describes a novel technique for the fast simulation of the forward calorimeter response, based on similarity search methods. Such techniques constitute a branch of ML and include clustering and indexing methods that enable quick and efficient searches for vectors similar to each other. The new simulation approach provides optimal results in terms of detector resolution response and reduces the computational requirements of a standard particles simulation.

A Search for Exotic Higgs Decays

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Publisher : Springer Nature
ISBN 13 : 3031304667
Total Pages : 201 pages
Book Rating : 4.0/5 (313 download)

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Book Synopsis A Search for Exotic Higgs Decays by : Jackson Burzynski

Download or read book A Search for Exotic Higgs Decays written by Jackson Burzynski and published by Springer Nature. This book was released on 2023-05-23 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: The absence of new physics at the TeV scale observed thus far at the Large Hadron Collider (LHC) motivates an increasing focus on searches for weakly-coupled new particles and exotic signatures. In particular, particles with macroscopic mean proper lifetimes, known as long-lived particles (LLPs), are of significant interest due to their ability to elude the majority of searches which rely on the assumption that Beyond Standard Model particles decay close to the primary interaction point. Many models which aim to solve various issues with the Standard Model (SM) introduce new particles with lifetimes that are either unconstrained, or even shown to prefer the macroscopic regime. These theories often point to the Higgs boson as a possible portal to new physics, with exotic Higgs decays being the primary phenomenological consequence and means of discovery. It is well motivated both from theory and experimental constraints to consider the scenario in which the particles produced in these exotic decays have macroscopic proper lifetimes and give rise to unique detector signatures. This work describes a search for exotic decays of the Higgs boson to two long-lived, neutral, spin-0 particles which subsequently decay to pairs of b quarks, giving the striking signature of displaced hadronic jets in the ATLAS inner detector. Several other ATLAS searches have probed this decay topology previously, excluding branching ratios of the Higgs boson to LLPs of more than 10% for proper lifetimes greater than 100mm. These searches relied on dedicated triggers designed to select events with LLPs decaying in the ATLAS calorimeter or muon spectrometer. The lack of an equivalent trigger for LLP decays in the ATLAS inner detector has been a limiting factor in probing LLP lifetimes less than 100mm. To circumvent the difficulty of triggering on LLP decays, the search presented in this thesis exploits the ZH associated production mode, relying on leptonic trigger signatures to select interesting events. This is the first search for Higgs boson decays into LLPs to exploit this analysis methodology and additionally makes use of several novel methods for both background rejection and background estimation. No excess over Standard Model predictions is observed, and upper limits are set on the branching ratio of the Higgs boson to LLPs . Depending on the mass of the LLP, branching ratios greater than 10% are excluded for lifetimes as small as 4mm and as large as 100mm, probing an important gap in the ATLAS exotic Higgs decay programme. In comparison to the previous searches for Higgs decays to LLPs, these are among the most stringent limits placed on this scenario, and for LLPs with masses below 40 GeV these results represent the strongest existing constraints on the branching ratio of the Higgs boson to LLPs in this lifetime regime.

Quantum Waveguides

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Author :
Publisher : Springer
ISBN 13 : 3319185764
Total Pages : 398 pages
Book Rating : 4.3/5 (191 download)

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Book Synopsis Quantum Waveguides by : Pavel Exner

Download or read book Quantum Waveguides written by Pavel Exner and published by Springer. This book was released on 2015-05-31 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph explains the theory of quantum waveguides, that is, dynamics of quantum particles confined to regions in the form of tubes, layers, networks, etc. The focus is on relations between the confinement geometry on the one hand and the spectral and scattering properties of the corresponding quantum Hamiltonians on the other. Perturbations of such operators, in particular, by external fields are also considered. The volume provides a unique summary of twenty-five years of research activity in this area and indicates ways in which the theory can develop further. The book is fairly self-contained. While it requires some broader mathematical physics background, all the basic concepts are properly explained and proofs of most theorems are given in detail, so there is no need for additional sources. Without a parallel in the literature, the monograph by Exner and Kovarik guides the reader through this new and exciting field.