Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Search For The Supersymmetric Partner To The Top Quark In The All Hadronic Final State With The Atlas Detector
Download Search For The Supersymmetric Partner To The Top Quark In The All Hadronic Final State With The Atlas Detector full books in PDF, epub, and Kindle. Read online Search For The Supersymmetric Partner To The Top Quark In The All Hadronic Final State With The Atlas Detector ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Search for the Supersymmetric Partner to the Top Quark in the All-hadronic Final State with the ATLAS Detector by : Matthew Anthony
Download or read book Search for the Supersymmetric Partner to the Top Quark in the All-hadronic Final State with the ATLAS Detector written by Matthew Anthony and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Search for the Supersymmetric Partner of the Top Quark with the ATLAS Detector Via $\tildet}^{}_{1} \rightarrow T \widetilde\chi}^{0}_{1}$ and $\tildet}^{}_{1} \rightarrow B \widetilde\chi}^{\pm}_{1}$ Decays by : Francesca Consiglia Ungaro
Download or read book Search for the Supersymmetric Partner of the Top Quark with the ATLAS Detector Via $\tildet}^{}_{1} \rightarrow T \widetilde\chi}^{0}_{1}$ and $\tildet}^{}_{1} \rightarrow B \widetilde\chi}^{\pm}_{1}$ Decays written by Francesca Consiglia Ungaro and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Zusammenfassung: The elementary particles composing matter and their interactions are described by the Standard Model of particle physics. The Standard Model of particle physics enabled predictions that were experimentally verified and has been confirmed throughout the past decades by data. Nevertheless, there are several theoretical reasons not to consider it as the ultimate theory.The strongest motivation to expect Physics beyond the Standard Model is the hierarchy problem. The radiative corrections to the mass of the Higgs boson grow quadratically with the square of the energy scale at which the Standard Model is considered to be valid. As a result, the parameters of the Standard Model need to be fine-tuned in order for the mass of the Higgs boson to acquire the value experimentally measured, despite the possibly large corrections.Supersymmetry is a promising theory extending the Standard Model which solves many of its shortcomings, including the hierarchy problem. Supersymmetry postulates a new fermion-boson symmetry resulting in the introduction of new particles, called superpartners, with the same quantum numbers and masses as the Standard Model particles, except for the spin, differing by half a unit. This new symmetry enables a cancellation of the radiative corrections due to the Standard Model particles with the corrections due to the newly introduced superpartners, contributing with opposite sign. Since no superpartners with the same mass as the Standard Model particles have been observed, Supersymmetry must be broken to allow the superpartners to have a mass different from the mass of the corresponding Standard Model particles.In the minimal version of Supersymmetry in terms of new particles, the Minimal Supersymmetric Standard Model, the hierarchy problem can still be solved with a moderate amount of fine-tuning if the masses of at least some of the superpartners are at the TeV energy scale. The conservation of a new multiplicative quantum number, the R-parity, can be assumed to prevent phenomena in contrast with experimental evidences, as the proton decay. Superpartners have R-parity -1, and Standard Model particles R-parity +1. If the conservation of R-parity is assumed, in collider experiments supersymmetric particles can only be produced in even numbers (usually two), and the lightest supersymmetric particles (LSP, usually taken to be the neutralino), is stable.The LHC (Large Hadron Collider), is a hadron collider able to accelerate protons to unprecedented energies. Between 2010 and 2012 it operated at a centre-of-mass energy of the proton-proton collisions of 7 and 8 TeV.Its general-purpose experiments, ATLAS (A Toroidal LHC Apparatus) and CMS (Compact Muon Spectrometer) collected data corresponding to about 5 $fb^{-1}$ at $\sqrt{s}$ = 7 TeV and 20 $fb^{-1}$ at $\sqrt{s}$ = 8 TeV. The LHC and its experiments have been built with the main motivations of searching for the Higgs boson, discovered by the ATLAS and CMS experiments in 2012, and searching for signals of Supersymmetry.There are strong theoretical reasons to expect the supersymmetric particles to lie at the TeV energy scale, which would make them accessible at the LHC.In the Minimal Supersymmetric Standard Model, the lightest superpartner of the top quark, light stop is very likely to be lighter than the superpartners of the other quarks. This thesis focuses on the search for direct stop pair production with the data collected by the ATLAS experiment. Two analyses have been performed, addressing different final states and decay modes.The first analysis targets stop masses close to the mass of the top quark, ideal to solve the hierarchy problem.The mass spectrum assumed is such that m(stop)
Book Synopsis The Search for Supersymmetry in Hadronic Final States Using Boosted Object Reconstruction by : Giordon Stark
Download or read book The Search for Supersymmetry in Hadronic Final States Using Boosted Object Reconstruction written by Giordon Stark and published by Springer Nature. This book was released on 2020-03-13 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis represents one of the most comprehensive and in-depth studies of the use of Lorentz-boosted hadronic final state systems in the search for signals of Supersymmetry conducted to date at the Large Hadron Collider. A thorough assessment is performed of the observables that provide enhanced sensitivity to new physics signals otherwise hidden under an enormous background of top quark pairs produced by Standard Model processes. This is complemented by an ingenious analysis optimization procedure that allowed for extending the reach of this analysis by hundreds of GeV in mass of these hypothetical new particles. Lastly, the combination of both deep, thoughtful physics analysis with the development of high-speed electronics for identifying and selecting these same objects is not only unique, but also revolutionary. The Global Feature Extraction system that the author played a critical role in bringing to fruition represents the first dedicated hardware device for selecting these Lorentz-boosted hadronic systems in real-time using state-of-the-art processing chips and embedded systems.
Book Synopsis The Search for Direct Top-squark Production in Hadronic Final States with the ATLAS Detector at [square Roots]s by : Christian Lüdtke
Download or read book The Search for Direct Top-squark Production in Hadronic Final States with the ATLAS Detector at [square Roots]s written by Christian Lüdtke and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Supersymmetry poses one of the best motivated theories for particle physics beyond the Standard Model. It can provide a dark matter candidate and enable grand unification. The supersymmetric partner of the top quark, the top squark, can provide a cancellation of diverging radiative corrections to the Higgs-boson mass and thereby avoid the hierarchy problem of the Standard Model. In this thesis, a search for top squarks in final states with jets and missing transverse momentum is presented. Proton-proton collisions at a centre-of-mass energy of √s = 13 TeV, produced by the Large Hadron Collider, were recorded by the ATLAS detector. The analysed dataset corresponds to an integrated luminosity of 36.1 fb-1. No significant excess above the Standard Model background was observed. The analysis results are interpreted as exclusion limits on the top-squark mass and the neutralino mass in various scenarios that address specific aspects of the supersymmetry
Book Synopsis The Search for Supersymmetry in Hadronic Final States Using Boosted Object Reconstruction by : Giordon Holtsberg Stark
Download or read book The Search for Supersymmetry in Hadronic Final States Using Boosted Object Reconstruction written by Giordon Holtsberg Stark and published by . This book was released on 2018 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Large Hadron Collider (LHC) operates at the highest energy scales ever artificially created in particle collision experiments with a center-of-mass energy √s = 13 TeV. In addition, the high luminosity allows the unique opportunity to probe the Standard Model at the electroweak scale and explore for rare signs of new physics beyond the Standard Model. The coupling of the third-generation top quark to the Higgs boson introduces large, quadratic, radiative corrections to the Higgs mass, requiring a significant amount of fine-tuning that results in a nearly perfect correction of the Higgs mass from the Planck scale to the observable electroweak scale. A possible solution to the naturalness problem proposes a collection of supersymmetric partners to the Standard Model particles with the mass of lightest particles at the electroweak scale: the gluino, the stop squarks, and the lightest supersymmetric particle. This thesis presents the results of a search for gluino pair production decaying via stop squarks to the lightest neutralino in hadronic final states using a total integrated luminosity 36.1 fb‒1 of data collected with the ATLAS detector in 2015 and 2016. This analysis considers a simplified supersymmetry model targeting extreme regions of the phase space with large missing transverse momentum, multiple b-tagged jets, and several energetic jets. No excess is observed and limits on the gluino mass are set at the 95% CL, greatly extending the previous results in 2012 from 1.4 TeV to 1.9 TeV. The increase of the LHC luminosity also poses challenges to the current trigger system in the ATLAS detector necessitating planned upgrades. One of the upgrades for the trigger system is the Global Feature Extractor (gFEX) which aims to recover lost efficiency in boosted hadronic final states by identifying large radius jets produced by top quarks, Higgs, Z and W bosons which are critical for future ATLAS physics programs. This module is a unique board with 3 processor FPGAs for data processing and an embedded multi-processor system-on-chip for slow-control and monitoring. This thesis will also describe the work on developing this hardware and several physics upgrade studies on the trigger performance.
Book Synopsis Third generation SUSY and t ̄t +Z production by : Josh McFayden
Download or read book Third generation SUSY and t ̄t +Z production written by Josh McFayden and published by Springer. This book was released on 2014-06-06 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes searches for new particles predicted by the super symmetry (SUSY) theory, a theory extending beyond the current Standard Model of particle physics, using the ATLAS detector at the CERN Large Hadron Collider. The thesis focuses on searches for stop and sbottom squarks, the SUSY partners of the top and bottom quarks, which are expected to be lighter than the partners of the first and second generation quarks and therefore good candidates for the first evidence of SUSY. It describes novel techniques for estimating and rejecting the Standard-Model backgrounds to searches for these particles. It also includes an independent analysis seeking to constrain the Standard Model ttZ background process, which also represents the first ATLAS search for this rare process at the LHC. The stop squark analysis described, with substantial leading contributions from the author, is the first search for these particles at the LHC to use the jets plus missing transverse energy plus 0-lepton signature and provides the world's best limits on the stop mass for light neutralino LSPs. All in all, the thesis describes three different world-leading analyses in both Standard Model and SUSY physics and therefore represents a major contribution to the field.
Book Synopsis Search for a Scalar Partner of the Top Quark in the All-hadronic [tau][tau][over-bar] Plus Missing Transverse Momentum Final State at [square Root]s TeV with the ATLAS Detector by : ATLAS Collaboration CERN
Download or read book Search for a Scalar Partner of the Top Quark in the All-hadronic [tau][tau][over-bar] Plus Missing Transverse Momentum Final State at [square Root]s TeV with the ATLAS Detector written by ATLAS Collaboration CERN and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Beyond Standard Model Collider Phenomenology of Higgs Physics and Supersymmetry by : Marc Christopher Thomas
Download or read book Beyond Standard Model Collider Phenomenology of Higgs Physics and Supersymmetry written by Marc Christopher Thomas and published by Springer. This book was released on 2016-08-01 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Book Synopsis Advances in Jet Substructure at the LHC by : Roman Kogler
Download or read book Advances in Jet Substructure at the LHC written by Roman Kogler and published by Springer Nature. This book was released on 2021-05-10 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the reader to the field of jet substructure, starting from the basic considerations for capturing decays of boosted particles in individual jets, to explaining state-of-the-art techniques. Jet substructure methods have become ubiquitous in data analyses at the LHC, with diverse applications stemming from the abundance of jets in proton-proton collisions, the presence of pileup and multiple interactions, and the need to reconstruct and identify decays of highly-Lorentz boosted particles. The last decade has seen a vast increase in our knowledge of all aspects of the field, with a proliferation of new jet substructure algorithms, calculations and measurements which are presented in this book. Recent developments and algorithms are described and put into the larger experimental context. Their usefulness and application are shown in many demonstrative examples and the phenomenological and experimental effects influencing their performance are discussed. A comprehensive overview is given of measurements and searches for new phenomena performed by the ATLAS and CMS Collaborations. This book shows the impressive versatility of jet substructure methods at the LHC.
Book Synopsis Searches for the Supersymmetric Partner of the Top Quark, Dark Matter and Dark Energy at the ATLAS Experiment by : Nicolas Maximilian Köhler
Download or read book Searches for the Supersymmetric Partner of the Top Quark, Dark Matter and Dark Energy at the ATLAS Experiment written by Nicolas Maximilian Köhler and published by Springer Nature. This book was released on 2019-09-13 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astrophysical observations implying the existence of Dark Matter and Dark Energy, which are not described by the Standard Model (SM) of particle physics, have led to extensions of the SM predicting new particles that could be directly produced at the Large Hadron Collider (LHC) at CERN. Based on 2015 and 2016 ATLAS proton-proton collision data, this thesis presents searches for the supersymmetric partner of the top quark, for Dark Matter, and for DarkEnergy, in signatures with jets and missing transverse energy. Muon detection is key to some of the most important LHC physics results, including the discovery of the Higgs boson and the measurement of its properties. The efficiency with which muons can be detected with the ATLAS detector is measured using Z boson decays. The performance of high-precision Monitored Drift Tube muon chambers under background rates similar to the ones expected for the High Luminosity-LHC is studied.
Book Synopsis Search for Supersymmetry in the All-hadronic Final State Using Top Quark Tagging in Pp Collisions at Sqrt(s) by :
Download or read book Search for Supersymmetry in the All-hadronic Final State Using Top Quark Tagging in Pp Collisions at Sqrt(s) written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A search is presented for supersymmetry in all-hadronic events with missing transverse momentum based on tagging of top quarks. The data sample corresponds to an integrated luminosity of 2.3 inverse femtobarns of proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC. Search regions are defined using the properties of reconstructed jets, the presence of bottom and top quark candidates, and an imbalance in transverse momentum. With no statistically significant excess of events observed beyond the expected contributions from the standard model, we set exclusion limits at 95% confidence level on the masses of new particles in the context of simplified models of direct and gluino-mediated top squark production. For direct top squark production with decays to a top quark and a neutralino, top squark masses up to 740 GeV and neutralino masses up to 240 GeV are excluded. Gluino masses up to 1550 GeV and neutralino masses up to 900 GeV are excluded for models of gluino pair production where each gluino decays to a top-antitop quark pair and a neutralino.
Book Synopsis Search for New Physics in tt ̅ Final States with Additional Heavy-Flavor Jets with the ATLAS Detector by : Javier Montejo Berlingen
Download or read book Search for New Physics in tt ̅ Final States with Additional Heavy-Flavor Jets with the ATLAS Detector written by Javier Montejo Berlingen and published by Springer. This book was released on 2016-07-20 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: This doctoral thesis focuses on the search for new phenomena in top-antitop quark (tt) final states with additional b-quark jets at the LHC. It uses the full Run 1 dataset collected by the ATLAS experiment in proton-proton collisions at √s=8 TeV. The final state of interest consists of an isolated lepton, a neutrino and at least six jets with at least four b-tagged jets, a challenging experimental signature owing to the large background from tt+heavy-flavor production. This final state is characteristic of ttH production, with the Higgs boson decaying into bb, a process that allows direct probing of the top-Higgs Yukawa coupling. This signature is also present in many extensions of the Standard Model that have been proposed as solutions to the hierarchy problem, such as supersymmetry or composite Higgs models, which predict the pair production of bosonic or fermionic top quark partners, or the anomalous production of four-top-quark events. All these physics processes have been searched for using an ambitious search strategy that has been developed on the basis of a combination of state-of-art theoretical predictions and a sophisticated statistical analysis to constrain in-situ the large background uncertainties. As a result, the most restrictive bounds to date on the above physics processes have been obtained.
Book Synopsis Search for New Phenomena with Top Quark Pairs in Final States with One Lepton, Jets, and Missing Transverse Momentum in Pp Collisions at [square Root]s by : ATLAS Collaboration CERN
Download or read book Search for New Phenomena with Top Quark Pairs in Final States with One Lepton, Jets, and Missing Transverse Momentum in Pp Collisions at [square Root]s written by ATLAS Collaboration CERN and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: A search for new phenomena with top quark pairs in final states with one isolated electron or muon, multiple jets, and large missing transverse momentum is performed. Signal regions are designed to search for two-, three-, and four-body decays of the directly pair-produced supersymmetric partner of the top quark (stop). Additional signal regions are designed specifically to search for spin-0 mediators that are produced in association with a pair of top quarks and decay into a pair of dark-matter particles. The search is performed using the Large Hadron Collider proton-proton collision dataset at a centre-of-mass energy of s√ = 13 TeV recorded by the ATLAS detector from 2015 to 2018, corresponding to an integrated luminosity of 139 fb−1. No significant excess above the Standard Model background is observed, and limits at 95% confidence level are set in the stop-neutralino mass plane and as a function of the mediator mass or the dark-matter particle mass. Stops are excluded up to 1200 GeV (710 GeV) in the two-body (three-body) decay scenario. In the four-body scenario stops up to 640 GeV are excluded for a stop-neutralino mass difference of 60 GeV. Scalar and pseudoscalar dark-matter mediators are excluded up to 200 GeV when the coupling strengths of the mediator to Standard Model and dark-matter particles are both equal to one and when the mass of the dark-matter particle is 1 GeV
Book Synopsis Search for a Supersymmetric Partner of the Top Quark in the One-lepton Channel with the ATLAS Detector by : Kilian Rosbach
Download or read book Search for a Supersymmetric Partner of the Top Quark in the One-lepton Channel with the ATLAS Detector written by Kilian Rosbach and published by . This book was released on 2015 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Search for the Top-quark Supersymmetric Partner in Di-lepton Final States with the ATLAS Experiment by : Maria Elena Stramaglia
Download or read book Search for the Top-quark Supersymmetric Partner in Di-lepton Final States with the ATLAS Experiment written by Maria Elena Stramaglia and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Search for Dark Matter with the ATLAS Detector by : Johanna Gramling
Download or read book Search for Dark Matter with the ATLAS Detector written by Johanna Gramling and published by Springer. This book was released on 2018-08-01 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses searches for Dark Matter at the CERN’s LHC, the world’s most powerful accelerator. It introduces the relevant theoretical framework and includes an in-depth discussion of the Effective Field Theory approach to Dark Matter production and its validity, as well as an overview of the formalism of Simplified Dark Matter models. Despite overwhelming astrophysical evidence for Dark Matter and numerous experimental efforts to detect it, the nature of Dark Matter still remains a mystery and has become one of the hottest research topics in fundamental physics. Two searches for Dark Matter are presented, performed on data collected with the ATLAS experiment. They analyze missing-energy final states with a jet or with top quarks. The analyses are explained in detail, and the outcomes and their interpretations are discussed, also in view of the precedent analysis of theoretical approaches. Given its depth of coverage, the book represents an excellent reference guide for all physicists interested in understanding the theoretical and experimental considerations relevant to Dark Matter searches at the LHC.
Book Synopsis Search for Supersymmetry in Final States with Multiple Bottom Quarks with the ATLAS Detector by : Meisam Ghasemi Bostanabad
Download or read book Search for Supersymmetry in Final States with Multiple Bottom Quarks with the ATLAS Detector written by Meisam Ghasemi Bostanabad and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The theoretical development of the Standard Model in the 1960s and 1970s has led to the discovery of its missing piece, the Higgs boson, at the ATLAS experiment (together with its sister experiment, CMS) at the Large Hadron Collider at CERN in 2012. In order to solve the problem of large quantum corrections to the leading expansion of the Higgs boson mass, additional symmetries need to be added to the Standard Model. A possible solution to this problem of Higgs mass quantum corrections is the theory of Supersymmetry, which includes partners to each Standard Model particle, such as gluinos, squarks, and the lightest supersymmetric particle. This dissertation describes a search for pair-produced gluinos, where each gluino decays via a top squark or a bottom squark to the lightest supersymmetric particle (a neutralino). Events which contain a large jet multiplicity in the final state (i.e. at least four jets of which at least three must be b-jets), and large amounts of missing transverse energy, are obtained for further studies. The dataset used for this search includes 139 fb^−1 of integrated luminosity recorded by the ATLAS experiment between 2015 and 2018 at a center-of-mass energy √s = 13 TeV. No significant excess is observed in data above the Standard Model backgrounds, and gluino masses up to 2.3 TeV for both the Gtt and the Gbb models are excluded at a 95% confidence level. This dissertation also contains an overview of, and the author's work on, the data quality monitoring of the ATLAS liquid argon calorimeter during 2017 data taking.
![Download The Search for Direct Top-squark Production in Hadronic Final States with the ATLAS Detector at [square Roots]s PDF Online Free](https://books.google.com/books/content/images/frontcover/4b3HzQEACAAJ?fife=w200-h370)
![Download Search for a Scalar Partner of the Top Quark in the All-hadronic [tau][tau][over-bar] Plus Missing Transverse Momentum Final State at [square Root]s TeV with the ATLAS Detector PDF Online Free](https://books.google.com/books/content/images/frontcover/cp-fzwEACAAJ?fife=w200-h370)
![Download Search for New Phenomena with Top Quark Pairs in Final States with One Lepton, Jets, and Missing Transverse Momentum in Pp Collisions at [square Root]s PDF Online Free](https://books.google.com/books/content/images/frontcover/ujimzwEACAAJ?fife=w200-h370)
