Download or read book Search for CP Violation in Top Quark Pair with Lepton jets Final State at s written by 莊振宇 and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Search for CP Violation Using Top Quark antiquark Events in the Lepton jets Channel in Pp Collisions with s written by 陳溥生 and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Search for CP Violation in Top Quark antiquark Production and Decay in Proton proton Collisions at sqrt s written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of a first search for CP violation in the production and decay of top quark-antiquark (ttbar) pairs are presented. The search is based on asymmetries in T-odd, triple-product correlation observables, where T is the time-reversal operator. The analysis uses a sample of proton-proton collisions at $\sqrt{s}$ TeV collected by the CMS experiment, corresponding to an integrated luminosity of 19.7 inverse femtobarns. Events are selected having one electron or muon and at least four jets. The T-odd observables are measured using four-momentum vectors associated with ttbar production and decay. The measured asymmetries exhibit no evidence for CP-violating effects, consistent with the expectation from the standard model.
Download or read book New Era For Cp Asymmetries Axions And Rare Decays Of Hadrons And Leptons written by Ikaros I Bigi and published by World Scientific. This book was released on 2021-07-14 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is dedicated to Lev Okun, who passed away in November 2015. He was a true pioneer in probing fundamental dynamics.The book has two objectives. First is to showcase Okun's impact for decades since 1963, when he published his remarkable book Weak Interaction of Elementary Particles. Second is to present the current progress of our scientific community in the studies of our Universe. New directions and possible future developments are discussed, often using the past as a guide. The authors mostly focus on CP asymmetries in the transitions of hadrons and leptons, but they also discuss their rare decays, and talk about axions and supersymmetry, and possible connections with dark matter, extra dimensions, baryogenesis and multiverse.This book is suitable for readers who know quantum mechanics and quantum field theories in general.
Download or read book CP Violating Anomalous Top quark Coupling in P bar p Collision at sqrt s written by and published by . This book was released on 2011 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: We conduct the first study of the T-odd correlations in tt events produced in p$\bar{p}$ collision at the Fermilab Tevatron collider that can be used to search for CP violation. We select events which have lepton+jets final states to identify t$\bar{t}$ events and measure counting asymmetries of several physics observables. Based on the result, we search the top quark anomalous couplings at the production vertex at the Tevatron. In addition, Geant4 development, photon identification, the discrimination of a single photon and a photon doublet from ?0 decay are discussed in this thesis.
Download or read book CP Violation in Single Top Quark Production written by and published by . This book was released on 2012 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a search for CP violation in single top quark production with the DØ experiment at the Tevatron proton-antiproton collider. CP violation in the top electroweak interaction results in different single top quark production cross sections for top and antitop quarks. We perform the search in the single top quark final state using 5.4 fb-1 of data, in the s-channel, t-channel, and for both combined. At this time, we do not see an observable CP asymmetry.
Download or read book Cp Violation written by Cecilia Jarlskog and published by World Scientific. This book was released on 1989-01-01 with total page 733 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contents:CP Phenomenology:Introduction to CP Violation (C Jarlskog)CP-Violation in the K0-K0-System (K Kleinknecht)The Quark Mixing Matrix, Charm Decays and B Decays (S Stone)The Question of CP Noninvariance — As Seen through the Eyes of Neutral Beauty (I I Bigi et al.)In Search of CP Noninvariance in Heavy Quark Systems (L-L Chau)CP Violation at High Energy e+e- Colliders (J Bernabéu & M B Gavela)CP Violation in the Standard Model with Four Families (A Datta & E A Paschos)CP Effects When Neutrinos are their Own Antiparticles (B Kayser)On Spontaneous CP Violation Triggered by Scalar Bosons (I I Bigi & A I Sanda)CP Violation and Left-Right Symmetry (R N Mohapatra)CP Violation and Supersymmetry (R N Mohapatra)Electric Dipole Moments (S M Barr & W H Marciano)Special Topics: The Strong CP Problem (R D Peccei)CP Violation and Cosmology (P Langacker)Nonleptonic Interactions:The 1/N Approach to Nonleptonic Weak Interactions (A J Buras)Chiral Perturbation Theory Approach to Weak Amplitudes (E de Rafael)What We Learnt from Weak Decays of Heavy Quarks (B Stech)Weak Hamiltonian on the Lattice (G Martinelli) Readership: High energy physicists. Keywords:CP Violation;Quark Mixing Matrix;Charm Decays;B Decays;Nonleptic Interactions;Heavy QuarksReview: “Similar material is most often available in journals, but the book accomplishes a valuable service in drawing it together … the one that will probably have the greatest utility and longest lifespan is the survey of B meson physics by I Bigi, V Khoze, N Uraltsev and A Sanda … Bigi et al. here provide the most thorough and readable account of the issues that I know of. I have seen no review comparable to the excellent summary of electric dipole moments by S Barr and W Marciano … the volume offers a generally readable entry into this field for a reader who has a basic background in particle physics.” John F Donoghue Science “… this book performs a very useful service for anyone active or interested in CP violation, both as a source of primary information and as a work of reference.” K J Peach J Phys. G: Nucl. Part. Phys.
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.
Download or read book CP Violation written by Società italiana di fisica and published by IOS Press. This book was released on 2006 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dealing with the CP violation, from quarks to leptons, this publication reviews the field, from both the theoretical and experimental point of view, while planning for the experimentation at LHC and considering possible facilities for kaon, B meson and neutrino physics.
Download or read book CP Violation in Single Top Quark Production written by Weigang Geng and published by . This book was released on 2012 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a search for CP violation in single top quark production with the DØ experiment at the Tevatron proton-antiproton collider. CP violation in the top electroweak interaction results in different single top quark production cross sections for top and antitop quarks. We perform the search in the single top quark final state using 5.4 fb-1 of data, in the s-channel, t-channel, and for both combined. At this time, we do not see an observable CP asymmetry.
Download or read book Search for Excited Top Quark Pair Production in Lepton Plus Jets Final State with s written by 陳以牧 and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Method for Measuring CP Violation in Top Quark Pair Production at ATLAS written by Fredric Kalen Martens and published by . This book was released on 2007 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Standard Model (SM) predicts that a large fraction of top quark pairs produced in 14 TeV center-of-mass pp collisions will have correlated helicities, and the number of tLt ̄ ̄ L and tRt ̄ ̄R pairs produced will be approximately equal. Unequal numbers of these pairs are an indication that CP symmetry is violated and there is new physics beyond the Standard Model. A method to measure CP violation in tt ̄ ̄ pair production at the Large Hadron Collider is presented. In particular, the value of DeltaNLR = [sigma(t Lt ̄ ̄L) - sigma(t Rt ̄ ̄R)]/sigma(tt ̄ ̄)TOT is found to be best measured in the lepton-plus-jets channel of tt ̄ ̄ decay. In this channel, the top pair can be reconstructed and the angular distribution of the leptons with respect to the top quark momentum can be determined. The ATLAS experiment can measure Delta NLR with a statistical uncertainty on the order of 3.5% using only 50 fb-1 of integrated luminosity. The sources of a number of systematic uncertainties were also studied. A method to detect CP violation in the dimuon decay channel using the P T asymmetry of oppositely charged muons was also investigated.
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.
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.
Download or read book Heavy Flavours written by A J Buras and published by World Scientific. This book was released on 1992-11-26 with total page 803 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is a collection of review articles on the most outstanding topics in heavy flavour physics. All the authors have made significant contributions to this field. The book reviews in detail the theoretical structure of heavy flavour physics within the Standard Model and its confrontation with existing experimental data.The physics of the top quark and of the Higgs play an important role in this volume. Beginning with radiative electroweak corrections and their impressive tests at LEP and hadron colliders, the book summarizes the present status of quark mixing, CP violation and rare decays. The dynamics of exclusive D- and B-meson decays, the τ-lepton physics and the newly discovered heavy quark symmetries are discussed in detail. The impact of strong interactions on weak decays is clearly visible in many articles. The physics of heavy flavours at LEP, HERA and hadron colliders constitutes an important part of the book. Another significant topic is the possible role of heavy flavours in the spontaneous symmetry breaking of gauge symmetries. Finally the most recent advances in lattice calculations of the properties of heavy flavours and the lattice studies of the dynamics of heavy flavours are presented.
Download or read book Search for Cp Violation in Top Quark antiquark Production and Decay in Proton proton Collisions written by 蔡瑞發 and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
