Effective Angular Momentum Operators in NRQED and Matching at One-Loop Order
arXiv:1012.3668 · doi:10.1007/JHEP02(2011)107
Abstract
We derive the effective angular momentum operator to $1/m^2$ and one-loop order in non-relativistic quantum electrodynamics (NRQED). In both dimensional and three-momentum-cutoff regularization schemes, we obtain the non-relativistic expansion for the spin and orbital angular momentum operators of the electron and photon, respectively. Our result is useful in precision calculations of the angular momentum properties for non-relativistic QED bound states, such as atom systems.
23 pages, 6 figures, 2 tables; published version