Volume 396 - The 38th International Symposium on Lattice Field Theory (LATTICE2021) - Oral presentation
Nucleon-pion-state contamination in lattice computations of the nucleon electromagnetic form factors
O. Baer* and H. Colic
Full text: pdf
Pre-published on: May 16, 2022
Published on:
Abstract
The nucleon-pion-state contributions to QCD two-point and three-point functions relevant for lattice calculations of the nucleon electromagnetic form factors are studied in chiral perturbation theory.
To leading order the results depend on a few experimentally known low-energy constants only, and the nucleon-pion-state contribution to the form factors can be estimated. The nucleon-pion-state contribution to the electric form factor $G_{\rm E}(Q^2)$ is at the +5 percent level for a source-sink separation of 2 fm, and it increases with increasing momentum transfer $Q^2$. For the magnetic form factor the nucleon-pion-state contribution leads to an underestimation of $G_{\rm M}(Q^2)$ by about $-5$ percent that decreases with increasing $Q^2$.
For smaller source-sink separations that are accessible in present-day lattice simulations the impact is larger. Although the ChPT results may not be applicable for these time separations a comparison with recent lattice data works reasonably well.
DOI: https://doi.org/10.22323/1.396.0455
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.