Related papers: Exclusive processes in position space and the pion…
We present a lattice QCD calculation of the double-virtual neutral pion transition form factor, with the goal to cover the kinematic range relevant to hadronic light-by-light scattering in the muon $g-2$. Several improvements have been made…
We develop a coordinate version of light-cone-ordered perturbation theory, for general time-ordered products of fields, by carrying out integrals over one light-cone coordinate for each interaction vertex. The resulting expressions depend…
We present the results of a lattice study of light-cone distribution amplitudes (DAs) of the nucleon and negative parity nucleon resonances using two flavors of dynamical (clover) fermions on lattices of different volumes and pion masses…
Results from the first lattice QCD analysis of vacuum correlators of local hadronic currents using dispersion relations are presented. We have explored the vector, pseudoscalar, axial, and scalar meson channels, and the proton-like and…
Measurements and theoretical calculations of meson form factors are essential for our understanding of internal hadron structure and QCD, the dynamics that bind the quarks in hadrons. The pion electromagnetic form factor has been measured…
An effective description of hadronic matter in terms of "effective free particles" is presented. Repulsive interactions among the hadrons have been modelled by Excluded volume correction by considering the hadrons as liquid drops, whose…
A reliable evaluation of the integral giving the hadronic vacuum polarization contribution to the muon anomalous magnetic moment should be possible using a simple trapezoid-rule integration of lattice data for the subtracted electromagnetic…
We investigate the leading twist light-cone distribution amplitudes (LCDAs) of vector meson in the framework of large momentum effective theory. We derive the matching equation for the LCDAs and quasi distribution amplitudes. The matching…
The masses and dispersions of light hadrons are calculated in lattice QCD using an O(a^2) tadpole-improved gluon action and an O(a^2) tadpole-improved next-nearest-neighbor fermion action originally proposed by Hamber and Wu. Two lattices…
We present a preliminary result for second moment of the light cone wave function of the pion. This parameter is the subject of a discrepancy between theoretical predictions (coming from lattice and sum rules) and a recent experimental…
A method for computing all-point quark propagators is applied to a variety of processes of physical interest in lattice QCD. The method allows, for example, efficient calculation of disconnected parts and full momentum-space 2 and 3 point…
The evolution of the pion distribution amplitude in next-to-leading order is studied for a fixed and a running coupling constant. In both cases, the evolution provides a logarithmic modification in the endpoint region. Assuming a simple…
We extend the epsilon-expansion of continuum chiral perturbation theory to nonzero lattice spacing in the framework of Wilson Chiral Perturbation Theory. We distinguish various regimes by defining the relative power counting of the quark…
We present the first attempt of a new method to compute the pion light-cone wave function (LCWF) on the lattice. We compute the matrix element between the pion and the vacuum of a non-local operator: the propagator of a ``scalar quark''…
Nuclear processes involving momenta much below the mass of the pion may be described by an effective field theory in which the pions do not appear as explicit degrees of freedom. The effects of the pion and all other virtual hadrons are…
We study the properties of pions in twisted mass lattice QCD (with two degenerate flavors) using chiral perturbation theory (ChPT). We work to next-to-leading order (NLO) in a power counting scheme in which m_q ~ a \Lambda_QCD^2, with m_q…
We discuss a number of old and new methods for computing $K\to\pi\pi$ amplitudes on the lattice. They all involve a non-perturbative determination of matching coefficients. We show how problems related to operator mixing can be greatly…
The pion light-cone distribution amplitude (LCDA) is a central non-perturbative object of interest for high-energy exclusive processes in quantum chromodynamics. In this article, the second Mellin moment of the pion LCDA is determined as a…
We consider the pion matrix elements of the isoscalar and isovector combinations of the vector and tensor twist-two operators that determine the moments of the various pion generalised parton distributions. Our analysis is performed using…
In this paper, we study the pion leading-twist distribution amplitude $\phi_{2;\pi}(x,\mu)$ by improving the traditional light-cone harmonic oscillator model within the reconstruction of the function $\varphi_{2;\pi}(x)$. In order to…