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arXiv · 1012.3668

Effective Angular Momentum Operators in NRQED and Matching at One-Loop Order

Panying Chen·Xiangdong Ji·Yue Zhang
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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.

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Panying Chen, Xiangdong Ji, Yue Zhang. 2010-12-16. Effective Angular Momentum Operators in NRQED and Matching at One-Loop Order. https://doi.org/10.1007/jhep02(2011)107

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