Forbidden transitions in the helium atom
نویسنده
چکیده
Nonrelativistically forbidden, single-photon transition rates between low lying states of the helium atom are rigorously derived within quantum electrodynamics theory. Equivalence of velocity and length gauges, including relativistic corrections is explicitly demonstrated. Numerical calculations of matrix elements are performed with the use of high precision variational wave functions and compared to former results. PACS numbers 31.30 Jv, 12.20 Ds, 32.70 Cs, 31.15 Md Typeset using REVTEX present address: Quantum Chemistry Laboratory, Warsaw University, Pasteura 1, 02-093 Warsaw, Poland
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