Relativistic effects in atomic structure theory

In heavy atomic systems, the electron wavefunction must be treated relativistically (Dirac equation) to accurately calculate atomic properties. The inter-electron Coulomb interaction, however, is still typically treated using a non-relativistic formalism. The lowest-order relativistic correction to the electron-electron repulsion is given by the Breit Hamiltonian (see, e.g., Ref. [1]), which accounts for magnetic and finite-speed-of-light effects.

This typically leads to only very small correction. However, for certain transitions in ionised atoms, the relativistic effects are expected to be greatly enhanced. This project would involve calculating Breit corrections to highly-charged ions, to determine if the lowest-order Breit correction is sufficient, or if new methods must be developed.

A strong theoretical understanding of the structure of ions is important for a number of applications, including high-precision tests of the Standard Model and electroweak theory at low energy, and searches for dark matter and exotic physics. Highly-charged ions are also great candidates for next-generating atomic clocks, and highly-accurate theoretical calculations are required to aid in their development.

[1] Bethe and Salpeter, Quantum Mechanics of One-and Two-Electron Atoms (1977).