Related papers: Systematics in nucleon matrix element calculations
This review focuses on the current status of lattice calculations of three observables which are both phenomenologically and experimentally relevant and have been scrutinized recently. These three observables are the nucleon electromagnetic…
These lectures give an introduction to the structure of the nucleon as seen with the electromagnetic probe. Particular emphasis is put on the form factors, the strangeness content, Compton scattering and polarizabilities, pion photo- and…
It is shown that the strong volume-dependence of the axial charge of the nucleon seen in lattice QCD calculations can be understood quantitatively in terms of the pion-induced interactions between neighbouring nucleons. The associated wave…
We numerically analyze the statistical properties of complex system with conditions subjecting the matrix elements to a set of specific constraints besides symmetry, resulting in various structures in their matrix representation. Our…
We calculate the scalar and tensor charges of the nucleon in 2+1-flavor lattice QCD, for which the systematics of the renormalization of the disconnected diagram is well controlled. Numerical simulations are performed at a single lattice…
Sea quark contributions to the scalar density and the axial current matrix elements of the nucleon are studied in lattice qcd with two flavours of dynamical wilson fermions. the results are compared to trends in heavy quark mass expansions,…
The comparison of chiral perturbation theory formulae with data from lattice QCD simulations is discussed. Observables in the pion sector as well as in the baryon sector are considered, including the nucleon mass in a finite volume.
The nucleon axial charge is a central ingredient in nuclear and particle physics, and a key observable in precision tests of the electroweak Standard Model sector and beyond. We report on the first complete calculation of its electroweak…
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…
Matrix elements of six-quark operators are needed to extract new physics constraints from experimental searches for neutron-antineutron oscillations. This work presents in detail the first lattice quantum chromodynamics calculations of the…
Using stochastic estimators for connected meson and baryon three-point functions has successfully been tried in the past years. Compared to the standard sequential source method we trade the freedom to compute the current-to-sink propagator…
We calculate shell-model matrix elements of the axial-charge exchange current operators that have been obtained up to the next-to-leading order from heavy-fermion chiral perturbation theory. It is found that loop corrections to the soft…
The exponentially falling signal-to-noise ratio in all nucleon correlation functions, and the presence of towers of multihadron excited states with relatively small mass gaps makes extraction of matrix elements of various operators within…
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…
Compton scattering offers in principle an intriguing new window on nucleon structure. Existing experiments and future programs are discussed and the state of theoretical understanding of such measurements is explored.
These lectures give an introduction to baryon chiral perturbation theory. I show in detail how to construct the chiral effective pion-nucleon Lagrangian in the one loop approximation. Particular emphasis is put on the physics related to…
We present a calculation of the three complex form factors parametrizing the nucleon to Delta transition matrix element in the framework of chiral effective field theory with explicit Delta degrees of freedom. The interplay between short…
Current matrix elements and observables for electro- and photo-excitation of baryons from the nucleon are studied in a light-front framework. Relativistic effects are examined by comparison to a nonrelativistic model and can typically be of…
In these proceedings we discuss recent progress in nucleon structure using lattice QCD simulations at or near the physical value of the pion mass. Main focus will be given in observables such as the nucleon axial charge and the first…
QCD matrix elements of axial and vector currents between nucleons are required for the Monte Carlo reconstruction of the energy of neutrinos that are detected in long baseline oscillation experiments in the quasi-elastic regime. The…