相关论文: Chiral extrapolation of nucleon axial charge $g_A$…
We study the quark mass expansion of the axial-vector coupling constant g_A of the nucleon. The aim is to explore the feasibility of chiral effective field theory methods for extrapolation of lattice QCD results - so far determined at…
We extrapolate lattice calculations of electric charge radii of the spin-1/2 baryon octet to the physical regime. The extrapolation procedure incorporates chiral perturbation theory and heavy quark effective theory in the appropriate…
The extrapolation of nucleon magnetic form factors calculated within lattice QCD is investigated within a framework based upon heavy baryon chiral effective-field theory. All one-loop graphs are considered at arbitrary momentum transfer and…
In this review I discuss the role of chiral extrapolations for the determination of several phenomenologically relevant quantities, including light quark masses, meson decay constants and the axial charge of the nucleon. In particular, I…
We report on recent work about the study of quark mass dependence of nucleon magnetic moments and axial-vector coupling constant. We examine the feasibility of chiral effective field theory methods for the extrapolation of lattice QCD data…
Lattice simulations for the electromagnetic form factors of the nucleon yield insights into the internal structure of hadrons. The logarithmic divergence of the charge radius in the chiral limit poses an interesting challenge in achieving…
We study the quark mass expansion of the magnetic moments of the nucleon in a chiral effective field theory including nucleons, pions and delta resonances as explicit degrees of freedom. We point out that the usual powercounting applied so…
An updated and extended analysis of the quark mass dependence of the nucleon's axial vector coupling constant g_A is presented in comparison with state-of-the-art lattice QCD results. Special emphasis is placed on the role of the…
Chiral effective field theory can provide valuable insight into the chiral physics of hadrons when used in conjunction with non-perturbative schemes such as lattice QCD. In this discourse, the attention is focused on extrapolating the mass…
The axial charge g_A is calculated in the epsilon regime of Heavy Baryon Chiral Perturbation Theory to order epsilon^3. To perform this calculation, we develop a technique to compute baryon properties in the epsilon regime of Chiral…
We report on our calculation of the nucleon axial charge gA in QCD with two flavours of dynamical quarks. A detailed investigation of systematic errors is performed, with a particular focus on contributions from excited states to…
We summarize developments concerning the quark mass dependence of nucleon magnetic moments and the axial-vector coupling constant g_A. The aim is to explore the feasibility of chiral effective field theory methods for the extrapolation of…
Two-nucleon axial charge and current operators are derived in chiral effective field theory up to one loop. The derivation is based on time-ordered perturbation theory, and accounts for cancellations between the contributions of irreducible…
We calculate the nucleon axial form factor up to the leading one-loop order in a covariant chiral effective field theory with the $\Delta(1232)$ resonance as an explicit degree of freedom. We fit the axial form factor to the latest lattice…
Proton spin is investigated in chiral effective field theory through an examination of the singlet axial charge, $a_0$, and the two non-singlet axial charges, $a_3$ and $a_8$. Finite-range regularization is considered as it provides an…
We extend the standard second order effective chiral Lagrangian of pions and nucleons by considering the coupling to an external gravitational field. As an application we calculate one-loop corrections to the one-nucleon matrix element of…
Using the expansion of the baryon wave function in a series of products of single quark bispinors (Dirac orbitals), the nonsinglet axial and tensor charges of a nucleon are calculated. The leading term yields $g_A = 1.27$ in good agreement…
Consideration of the analytical properties of pion-induced baryon self-energies leads to new functional forms for the extrapolation of light baryon masses. These functional forms reproduce the leading non-analytic behavior of chiral…
We present an updated analysis of the quark mass dependence of the nucleon mass and nucleon axial-vector coupling g_A, comparing different formulations of SU(2) Baryon Chiral Effective Field Theory, with and without explicit delta (1232)…
I discuss the conditions under which the application of chiral perturbation theory to the NN potential gives reliable results for NN scattering phase shifts. ChiPT also yields a convergent expansion for the deuteron charge operator. For…