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arXiv · 1212.4508

The NRQED lagrangian at order 1/M^4

Richard J. Hill·Gabriel Lee·Gil Paz·Mikhail P. Solon
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Abstract

The parity and time-reversal invariant effective lagrangian for a heavy fermion interacting with an abelian gauge field, i.e., NRQED, is constructed through order $1/M^4$. The implementation of Lorentz invariance in the effective theory becomes nontrivial at this order, and a complete solution for Wilson coefficient constraints is obtained. Matching conditions in the one-fermion sector are presented in terms of form factors and two-photon matrix elements of the nucleon. The extension of NRQED to describe interactions of the heavy fermion with a light fermion is introduced. Sample applications are discussed; these include the computation of nuclear structure effects in atomic bound states, the model-independent analysis of radiative corrections to low-energy lepton-nucleon scattering, and the study of static electromagnetic properties of nucleons.

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Richard J. Hill, Gabriel Lee, Gil Paz, Mikhail P. Solon. 2013-03-21. The NRQED lagrangian at order 1/M^4. https://doi.org/10.1103/physrevd.87.053017

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