Download or read book Exploring Quark Transverse Momentum Distributions with Lattice QCD written by and published by . This book was released on 2011 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: We discuss in detail a method to study transverse momentum dependent parton distribution functions (TMDs) using lattice QCD. To develop the formalism and to obtain first numerical results, we directly implement a bi-local quark-quark operator connected by a straight Wilson line, allowing us to study T-even, "process-independent" TMDs. Beyond results for x-integrated TMDs and quark densities, we present a study of correlations in x and transverse momentum. Our calculations are based on domain wall valence quark propagators by the LHP collaboration calculated on top of gauge configurations provided by MILC with 2+1 flavors of asqtad-improved staggered sea quarks.
Download or read book Transverse Momentum Dependent Quark Densities from Lattice QCD written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We study transverse momentum dependent parton distribution functions (TMDs) with non-local operators in lattice QCD, using MILC/LHPC lattices. We discuss the basic concepts of the method, including renormalization of the gauge link. Results obtained with a simplified operator geometry show visible dipole deformations of spin-dependent quark momentum densities.
Download or read book Transverse Momentum Distributions Inside the Nucleon from Lattice QCD written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We study transverse momentum dependent parton distribution functions (TMDs) with non-local operators in lattice QCD, using MILC/LHPC lattices. Results obtained with a simplified operator geometry show visible dipole deformations of spin-dependent quark momentum densities. We discuss the basic concepts of the method, including renormalization of the gauge link, and an extension to a more elaborate operator geometry that would allow us to analyze process-dependent TMDs such as the Sivers-function.
Download or read book Transverse Momentum dependent Parton Distribution Functions in Lattice QCD written by and published by . This book was released on 2013 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: A fundamental structural property of the nucleon is the distribution of quark momenta, both parallel as well as perpendicular to its propagation. Experimentally, this information is accessible via selected processes such as semi-inclusive deep inelastic scattering (SIDIS) and the Drell-Yan process (DY), which can be parametrized in terms of transversemomentum-dependent parton distributions (TMDs). On the other hand, these distribution functions can be extracted from nucleon matrix elements of a certain class of bilocal quark operators in which the quarks are connected by a staple-shaped Wilson line serving to incorporate initial state (DY) or final state (SIDIS) interactions. A scheme for evaluating such matrix elements within lattice QCD is developed. This requires casting the calculation in a particular Lorentz frame, which is facilitated by a parametrization of the matrix elements in terms of invariant amplitudes. Exploratory results are presented for the time-reversal odd Sivers and Boer-Mulders transverse momentum shifts.
Download or read book Transverse Momentum Distributions Inside the Nucleon from Lattice QCD written by Bernhard Ulrich Musch and published by . This book was released on 2009 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Parton Densities in Quantum Chromodynamics written by Igor Olegovich Cherednikov and published by Walter de Gruyter GmbH & Co KG. This book was released on 2016-11-21 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this book is to give a systematic pedagogical exposition of the quantitative analysis of Wilson lines and gauge-invariant correlation functions in quantum chromodynamics. Using techniques from the previous volume (Wilson Lines in Quantum Field Theory, 2014), an ab initio methodology is developed and practical tools for its implementation are presented. Emphasis is put on the implications of gauge invariance and path-dependence properties of transverse-momentum dependent parton density functions. The latter are associated with the QCD factorization approach to semi-inclusive hadronic processes, studied at currently operating and planned experimental facilities. Contents: Introduction Particle Number Operators in Quantum Mechanics and in Quantum Field Theory Geometry of Quantum Field Theories Basics of Wilson Lines in QCD Gauge-Invariant Parton Densities Simplifying Wilson Line Calculations Brief Literature Guide Conventions and Reference Formulae Integrations Bibliography Index
Download or read book QCD Higher Order Effects and Search for New Physics written by Jian Wang and published by Springer. This book was released on 2015-10-28 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book mainly investigates the precision predictions on the signal of new physics at the Large Hadron Collider (LHC) in the perturbative Quantum Chromodynamics (QCD) scheme. The potential of the LHC to discover the signal of dark matter associated production with a photon is studied after including next-to-leading order QCD corrections. The factorization and resummation of t-channel top quark transverse momentum distribution in the standard model at both the Tevatron and the LHC with soft-collinear effective theory are presented. The potential of the early LHC to discover the signal of monotops is discussed. These examples illustrate the method of searching for new physics beyond what is known today with high precision.
Download or read book Exploration of the Role of Diquarks in Hadrons Using Lattice QCD written by Patrick S. Varilly and published by . This book was released on 2006 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: We perform a number of measurements relevant to nuclear and particle physics by using the tools of lattice QCD. We verify our lattice calculations by reproducing published meson masses. We then study the light quark distribution in a meson with one heavy quark. After improving our methods in the meson case, we conclude by looking at the correlation between the two light quarks in a baryon. We find evidence for these quarks binding into spatially extended diquarks.
Download or read book Explorations of the Quark Substructure of the Nucleon in Lattice QCD written by Jonathan Daniel Bratt and published by . This book was released on 2009 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lattice gauge theory is a valuable tool for understanding how properties of the nucleon arise from the fundamental interactions of QCD. Numerical computations on the lattice can be used not only for first principles calculations of experimentally accessible quantities, but also for calculations of quantities that are not (yet) known from experiment. This thesis presents two lattice studies of the quark substructure of nucleons. The first study used overlaps calculated on the lattice to evaluate the goodness of trial nucleon sources. A variational study was performed to find the trial source that best approximated the true nucleon ground state. In this exploratory work with relatively simple trial sources on quenched lattices, we obtained overlaps as high as 80%. The second study was performed using domain wall valence fermions on Asqtad improved staggered lattices provided by the MILC collaboration, with pion masses as low as 290 MeV. We compute nucleon matrix elements of local quark operators: (F', S'l@P(0) F{Il Dt12 ... i D 0 (0)P, S), where F" E {y", -y"-y, -io*}. These operators are parameterized by generalized form factors, which in the infinite momentum frame can be unambiguously interpreted in terms of Fourier transforms of the transverse spatial distributions of quarks in a nucleon. By calculating the local operators at many different values of nucleon momentum, we extract a complete set of generalized form factors for the lowest two moments of the vector, axial and tensor operators. From the form factors, we compute a variety of quantities characterizing the internal structure of the nucleon. Finally, we explore chiral extrapolations of the lattice results to the physical pion mass.
Download or read book Quarks Leptons and Beyond written by H. Fritzsch and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 557 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ASI Quarks, Leptons and Beyond, held in Munich from the 5th to the 16th of September 1983 was dedicated to the study of what we now believe are the fundamental building blocks of nature: quarks and leptons. The subject was approached on two levels. On the one hand, a thorough discussion was given of the status of our knowledge of quarks and leptons and their interactions, both from an experi mental and a theoretical standpoint. On the other hand, open problems presented by the so called standard model of quark and lepton interact ions were explored along various ways that lead one beyond this frame work. One of the principal predictions of the standard model is that weak interactions are mediated by heavy Wand Z vector bosons. These particles were discovered in 1983 at CERN and their relevant proper ties were discussed at the ASI by C. Rubbia. Further theoretical predictions concerning these Z and W bosons, yet to be checked by future experimentation, were discussed by G. Altarelli with a view of seeing where the standard model might fail and new physics ensue. The strong interactions of quarks, based on Quantum Chromodynamics (QeD), are presumed to cause the quarks to bind into hadrons. Pro gress in attempts to calculate the observed hadronic spectrum, ab initio, starting from QCD and employing lattice methods were reviewed at the ASI by P. Hasenfratz.
Download or read book Foundations of Perturbative QCD written by John Collins and published by Cambridge University Press. This book was released on 2011-04-28 with total page 637 pages. Available in PDF, EPUB and Kindle. Book excerpt: Giving an accurate account of the concepts, theorems and their justification, this book is a systematic treatment of perturbative QCD. It relates the concepts to experimental data, giving strong motivations for the methods. Ideal for graduate students starting their work in high-energy physics, it will also interest experienced researchers.
Download or read book Nucleon Transverse Momentum dependent Parton Distributions from Domain Wall Fermion Calculations at 297 MeV Pion Mass written by and published by . This book was released on 2014 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, lattice QCD calculations of transverse momentum-dependent parton distributions (TMDs) in a nucleon are performed based on a definition of TMDs via hadronic matrix elements of quark bilocal operators containing staple-shaped gauge connections. A parametrization of the matrix elements in terms of invariant amplitudes serves to cast them in the Lorentz frame preferred for the lattice calculation. Using a RBC/UKQCD domain wall fermion ensemble corresponding to a pion mass of 297 MeV, on a lattice with spacing 0.084 fm, selected TMD observables are accessed and compared to previous exploration at heavier pion masses on coarser lattices.
Download or read book QCD Perspectives on Hot and Dense Matter written by Jean-Paul Blaizot and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many facets of quantum chromodynamics (QCD) are relevant to the in-depth discussion of theoretical and experimental aspects of high-energy nucleus-nucleus collisions. Exciting phenomena are being discovered in such ultrarelativistic heavy ion collisions, notably the increasingly important role of deconfined quark-gluon matter created in the early stage. The book contains lectures on the physics of hot dense matter, the expected phase transitions and colour superconductivity, recent developments in the treatment of nonlinear effects at large parton densities, fundamental issues in the phenomenology of ultrarelativistic heavy collisions. The latest data on heavy ion collisions are also presented. A unique collection of lectures on the many facets of QCD relevant to the physics of hot dense matter.
Download or read book Gribov 85 Memorial Volume Exploring Quantum Field Theory Proceedings Of The Memorial Workshop Devoted To The 85th Birthday Of V N Gribov written by Yuri L Dokshitzer and published by World Scientific. This book was released on 2016-09-16 with total page 549 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vladimir Naumovich Gribov is one of the creators of modern theoretical physics. The concepts and methods that Gribov has developed in the second half of the 20th century became cornerstones of the physics of high energy hadron interactions (relativistic theory of complex angular momenta, a notion of the vacuum pole — Pomeron, effective reggeon field theory), condensed matter physics (critical phenomena), neutrino oscillations, and nuclear physics.His unmatched insights into the nature of the quantum field theory helped to elucidate, in particular, the origin of classical solutions (instantons), quantum anomalies, specific problems in quantization of non-Abelian fields (Gribov anomalies, Gribov horizon), and the role of light quarks in the color confinement phenomenon.The fifth memorial workshop which marked Gribov's 85th birthday took place at the Landau Institute for Theoretical Physics, Russia, in June 2015. Participants of the workshop who came to Chernogolovka from different parts of the world presented new results of studies of many challenging theoretical physics problems across a broad variety of topics, and shared memories about their colleague, great teacher and friend.This book is a collection of the presented talks and contributed papers, which affirm the everlasting impact of Gribov's scientific heritage upon the physics of the 21st century.
Download or read book Multiple Parton Interactions at the LHC written by Paolo Bartalini and published by World Scientific Publishing. This book was released on 2018-11-08 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many high-energy collider experiments (including the current Large Hadron Collider at CERN) involve the collision of hadrons. Hadrons are composite particles consisting of partons (quarks and gluons), and this means that in any hadron–hadron collision there will typically be multiple collisions of the constituents — i.e. multiple parton interactions (MPI). Understanding the nature of the MPI is important in terms of searching for new physics in the products of the scatters, and also in its own right to gain a greater understanding of hadron structure. This book aims at providing a pedagogical introduction and a comprehensive review of different research lines linked by an involvement of MPI phenomena. It is written by pioneers as well as young leading scientists, and reviews both experimental findings and theoretical developments, discussing also the remaining open issues.
Download or read book Photon hadron Interactions written by Richard P. Feynman and published by Addison-Wesley Longman. This book was released on 1989-01-21 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analyzes the theoretical questions related to electron and photon interactions at high energies.
Download or read book Perspectives In Lattice Qcd Proceedings Of The Workshop written by Yoshinobu Kuramashi and published by World Scientific. This book was released on 2007-12-13 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book consists of a series of lectures to cover every facet of the modern version of lattice QCD. All the lectures are self-contained starting with the necessary background material and ending up with the latest development. Most of the lectures are given by pioneers in the field.This book may be useful as an advanced textbook for graduate students in particle physics and its modern and fascinating contents will inspire the interest of the non-experts.
