Download or read book Production of Top Quark Pairs in Association with a Hard Gluon to Order Alpha 2 S written by Arnd Brandenburg and published by . This book was released on 1999 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Production of Top Quark Pairs in Association with a Hard Gluon to Order alpha 2s alpha 2 S written by Arnd Brandenburg and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Production of Top Quark Pairs in Association with a Hard Gluon to Order 2s alpha 2 S written by Arnd Brandenburg and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heavy Quark Pair Production in Gluon Fusion at Next to next to leading 4s omicron alpha 4 S Order written by and published by . This book was released on 2008 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electroweak Gauginos with Highly Boosted Hadronically Decaying Bosons at the LHC written by Yuta Okazaki and published by Springer Nature. This book was released on 2023-01-01 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Supersymmetry (SUSY) introduces superpartners of the Standard Model (SM) particles. If their masses are typically O(100 GeV) ∼ O(TeV), a lightest neutralino can be a candidate for the dark matter, and the problem is solved by canceling the correction of the Higgs boson mass. Further, SUSY can explain the experimental result of the muon magnetic moment (g-2). This book presents a search for electroweakinos—the superpartners of the SM electroweak bosons—such as charginos and neutralinos using data at the LHC collected by the ATLAS detector. Pair-produced electroweakinos decay into the light ones and SM bosons (W/Z/h), and with the large mass difference between the heavy and light electroweakinos, the SM bosons have high momenta. In a fully hadronic final state, quarks decayed from the bosons are collimated, and can consequently be reconstructed as a single large-radius jet. This search has three advantages. The first is a statistical benefit by large branching ratios of the SM bosons. The second is to use characteristic signatures—the mass and substructure—of jets to identify as the SM bosons. The last is a small dependency on the signal model by targeting all the SM bosons. Thanks to them, the sensitivity is significantly improved compared to the previous analyses. Exclusion limits at the 95% confidence level on the heavy electroweakino mass parameter are set as a function of the light electroweakino mass parameter. They are set on wino or higgsino production models with various assumptions, such as the branching ratio of their decaying and the type of lightest SUSY particle. These limits are the most stringent limits. Besides, this book provides the most stringent constraints on SUSY scenarios motivated by the dark matter, the muon g-2 anomaly, and the naturalness.
Download or read book High Pt Physics at Hadron Colliders written by Dan Green and published by Cambridge University Press. This book was released on 2005 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Publisher Description
Download or read book Search for Flavor Changing Neutral Current Top Quark Decays t Hq with H bb in pp Collisions at s 8 TeV with the ATLAS Detector written by Shota Tsiskaridze and published by Springer. This book was released on 2017-08-02 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: This PhD thesis focuses on the search for flavor-changing neutral currents in the decay of a top quark to an up-type quark (q = u, c) and the Standard Model Higgs boson, where the Higgs boson decays to bb. Further, the thesis presents the combination of this search for top quark pair events with other ATLAS searches – in the course of which the most restrictive bounds to date on tqH interactions were obtained. Following on from the discovery of the Higgs boson, it is particularly important to measure the Yukawa couplings of the Standard Model fermions; these parameters may provide crucial insights to help solve the flavor puzzle and may help reveal the presence of new physics before it is directly observed in experiments.
Download or read book Heavy Quark Physics written by Aneesh V. Manohar and published by Cambridge University Press. This book was released on 2023-07-31 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study on the Top Quark Pair Production Mechanism in 1 96 TeV Proton antiproton Collisions written by and published by . This book was released on 2008 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of the top quark pair production mechanism in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV is described. The main subjects are the measurements of the top quark pair production cross section, the top quark mass and a search for a new particle decaying to the top quark pair. The analyses are based on 1.9 fb−1 of data collected by the Collider Detector at Fermilab (CDF) Run II experiment between March 2002 and May 2007, using the lepton+jets events. The measured top quark pair production cross section is 8.2 ± 0.5 (stat.) ± 0.8 (syst.) ± 0.5 (lum.) pb, which is slightly higher than the standard model prediction at the top mass of 175 GeV/c2. The top quark mass is an important parameter in the standard model, and also in the experimental studies. The measured top quark mass if 171.6 ± 2.0 (stat.) ± 1.3(syst.) GeV/c2. Finally, they report on a search for a new gauge boson decaying to t{bar t}, which interferes with the standard model gluon in the q{bar q} --> t{bar t} production process. They call such a hypothetical particle a 'Massive Gluon'. The observed t{bar t} invariant mass distribution is consistent with the standard model expectations, and also the measured massive gluon coupling strength with quarks is consistent within a statistical fluctuation of the standard model expectation in the wide range of the massive gluon masses and widths. They set the upper and lower limits on the coupling strength of the massive gluon.
Download or read book First Measurement of the Fraction of Top Quark Pair Production Through Gluon Gluon Fusion written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the first measurement of [sigma](gG → t{bar t})/[sigma](p{bar p} → t{bar t}). We use 0.96 fb−1 of √s = 1.96 TeV p{bar p} collision data recorded with the CDF II detector at Fermilab. We identify the candidate t{bar t} events with a high-energy charged lepton, a neutrino candidate, and four or more jets with at least one identified as originating from a b quark. Using charged particles with low transverse momentum in t{bar t} events, we find [sigma](gg → t{bar t})/[sigma](p{bar p} → t{bar t}) = 0.07 ± 0.14(stat) ± 0.07(syst), in agreement with the standard model NLO prediction of 0.15 ± 0.05.
Download or read book Heavy Quark Pair Production in Gluon Fusion at Next to next to leading O63 1hn4 1tns omicron alpha 4 S Order written by and published by . This book was released on 2008 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of Higgs Boson Production Cross Sections in the Diphoton Channel written by Ahmed Tarek Abouelfadl Mohamed and published by Springer Nature. This book was released on 2020-11-12 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the measurement of the Higgs boson cross section in the diphoton decay channel. The measurement relies on proton-proton collision data at a center-of-mass energy √s = 13 TeV recorded by the ATLAS experiment at the Large Hadron Collider (LHC). The collected data correspond to the full Run-2 dataset with an integrated luminosity of 139 fb-1. The measured cross sections are used to constrain anomalous Higgs boson interactions in the Effective Field Theory (EFT) framework. The results presented in this thesis represent a reduction by a factor 2 of the different photon and jet energy scale and resolution systematic uncertainties with respect to the previous ATLAS publication. The thesis details the calibration of electron and photon energies in ATLAS, in particular the measurement of the presampler energy scale and the estimation of its systematic uncertainty. This calibration was used to perform a measurement of the Higgs boson mass in the H → γγ and H → 4l channels using the 36 fb−1 dataset.
Download or read book Looking Inside Jets written by Simone Marzani and published by Springer. This book was released on 2019-05-11 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: This concise primer reviews the latest developments in the field of jets. Jets are collinear sprays of hadrons produced in very high-energy collisions, e.g. at the LHC or at a future hadron collider. They are essential to and ubiquitous in experimental analyses, making their study crucial. At present LHC energies and beyond, massive particles around the electroweak scale are frequently produced with transverse momenta that are much larger than their mass, i.e., boosted. The decay products of such boosted massive objects tend to occupy only a relatively small and confined area of the detector and are observed as a single jet. Jets hence arise from many different sources and it is important to be able to distinguish the rare events with boosted resonances from the large backgrounds originating from Quantum Chromodynamics (QCD). This requires familiarity with the internal properties of jets, such as their different radiation patterns, a field broadly known as jet substructure. This set of notes begins by providing a phenomenological motivation, explaining why the study of jets and their substructure is of particular importance for the current and future program of the LHC, followed by a brief but insightful introduction to QCD and to hadron-collider phenomenology. The next section introduces jets as complex objects constructed from a sequential recombination algorithm. In this context some experimental aspects are also reviewed. Since jet substructure calculations are multi-scale problems that call for all-order treatments (resummations), the bases of such calculations are discussed for simple jet quantities. With these QCD and jet physics ingredients in hand, readers can then dig into jet substructure itself. Accordingly, these notes first highlight the main concepts behind substructure techniques and introduce a list of the main jet substructure tools that have been used over the past decade. Analytic calculations are then provided for several families of tools, the goal being to identify their key characteristics. In closing, the book provides an overview of LHC searches and measurements where jet substructure techniques are used, reviews the main take-home messages, and outlines future perspectives.
Download or read book Heavy quark Pair Production in Gluon Fusion at Next to next to leading O a4s Order One loop Squared Contributions written by and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book QCD and Collider Physics written by R. K. Ellis and published by Cambridge University Press. This book was released on 2003-12-04 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed overview of the physics of high-energy colliders emphasising the role of QCD.
Download or read book Next to next to leading Order O alpha 2 alpha 2 S Results for Top Quark Pair Production in Photon photon Collisions written by Jürgen G. Körner and published by . This book was released on 2006 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Future Of High Energy Physics The Some Aspects written by Luis Roberto Flores Castillo and published by World Scientific. This book was released on 2017-02-20 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: The monumental discovery of the Higgs boson at the LHC marked the beginning of a new era in the high energy physics. Although the particle spectrum of the Standard Model is now complete with the Higgs boson, the hierarchy problem and the lack of explanation of the origin of dark matter imply that a new Beyond the Standard Model physics should exist. There is however no clear indication (experimental or otherwise) of the energy scale at which this new physics should appear. Current results from the LHC experiments have shown no unpredicted effects up to pp collision energies of 13 TeV. If not observed directly at the LHC, the new physics may reveal itself through deviations of Higgs properties from their Standard Model expectations, or it may become directly accessible only at new, higher-energy accelerator facilities. It is then of primary importance to have a comprehensive review of the available and planned accelerators and their design, physics motivation and expected performance.This book comprises 26 carefully edited articles with well-referenced and up-to-date material written by many of the leading experts. These articles — originated from presentations and dialogues at the second HKUST Institute for Advanced Study Program on High Energy Physics — are organized into three aspects, Theory, Accelerator, and Experiment, focusing on in-depth analyses and technical aspects that are essential for the developments and expectations for the future high energy physics.
