相关论文: Disconnected contributions to hadronic structure
A general approach for evaluating the nonfactorizable contributions to the hadronic matrix elements is described in terms of the higher twist wave functions of the mesons. An example is illustrated for the $B^{0} \to \pi^{+}\pi^{-}$ decays.
A review of recent nucleon structure calculations within lattice QCD is presented. The nucleon excited states, the axial charge, the isovector momentum fraction and helicity distribution are discussed, assessing the methods applied for…
We discuss methods for the calculation of disconnected diagrams and their application to various form factors of the nucleon. In particular, we present preliminary results for the strange contribution to the scalar and axial form factors,…
Developments in lattice field theory and computer technology have led to dramatic advances in the use of lattice QCD to explore the quark structure of hadrons. This talk will describe selected examples, including structure functions,…
We discuss the separation of isospin-symmetric and isospin-breaking contributions in the hadronic observables within the framework of QCD plus QED. Further, we briefly review some recent work on the low-energy hadron phenomenology, in which…
The structure of a dressed quark is utilized to evaluate the structure function of proton and pion. It is found that there is a simple relationship between $F_{2}^{p}$ and $F_{2}^{\pi}$. The ambiguity in the normalization of $F_{2}^{\pi}$…
This is a review of progress in hadron structure physics from lattice QCD. Recent results on the structure of the nucleon and the pion in terms of (transition) form factors, moments of distribution amplitudes and (generalized) parton…
We present recent developments in lattice QCD simulations as applied in the study of hadron structure. We discuss the challenges and perspectives in the evaluation of benchmark quantities such as the nucleon axial charge and the isovector…
In recent years the investigation of hadron structure using lattice techniques has attracted growing attention. In this talk we give an overview on recent work with a focus on results for nucleon spectrum and structure from the QCDSF…
We review recent progress in hadron structure using lattice QCD simulations, with main focus in the evaluation of nucleon quantities such as the axial and tensor charges, and the spin con- tent of the nucleon, using simulations at pion…
High-energy nucleon total cross sections are related to low-x DIS structure functions by using the additive quark model.
This review focuses on the discussion of three key results of nucleon structure calculations on the lattice. These three results are the quark contribution to the nucleon spin, J_q, the nucleon-Delta transition form factors, and the nucleon…
Results for the disconnected contributions to matrix elements of the vector current and scalar density have been obtained for the nucleon from the Wilson action at beta=6 using a stochastic estimator technique and 2000 quenched…
A review of recent lattice calculations of nucleon structure and matrix elements of operators in nucleons is presented. It primarily covers developments in the calculation of the matrix elements of the scalar, tensor, pseudo-scalar,…
We briefly review the status of our understanding of hadron structure based on QCD. This includes the role of symmetries, especially chiral symmetry, and the insights provided by lattice QCD. The main focus is on baryon structure and…
I present a review of the current status and the most recent achievements in lattice QCD calculations of hadron structure. First, I overview the status and systematic uncertainties of nucleon structure "benchmark" quantities that are well…
The spin structure of nucleon at twist 2 and 3 levels is analyzed. The contribution of quark and gluon spins to nucleon spin are Lorentz invariant, while it is not sure for orbital angular momentum. The conserved fractional moments of…
We show how quark-disconnected and quark-connected contributions to hadronic n-point functions can be written as independent correlators for which one can derive expressions in partially quenched chiral effective theory. As an example we…
We present results on the spin carried by quarks and gluons in the nucleon using lattice QCD simulations with physical values of the light, strange and charm quark masses. We also discuss selective results on the x-dependence of parton…
It is shown that intrinsic orbital motion of the valence quarks has large influences on the spin-dependent as well as the spin-averaged nucleon structure functions. Its connection with the observed ``very small contribution of quark spin to…