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Higher-order effective Hamiltonian for light atomic systems

Krzysztof Pachucki
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Abstract

We present the derivation of the effective higher-order Hamiltonian, which gives $m α^6$ contribution to energy levels of an arbitrary light atom. The derivation is based on the Foldy-Wouthuysen transformation of the one-particle Dirac Hamiltonian followed by perturbative expansion of the many particle Green function. The obtained results can be used for the high precision calculation of relativistic effects in atomic systems.

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Krzysztof Pachucki. 2004-11-18. Higher-order effective Hamiltonian for light atomic systems. https://doi.org/10.1103/physreva.71.012503

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