Determination of the Fine Structure Constant Using Helium Fine Structure

Fine Structure of Helium

Under the expectation that experiments will soon give values for the 6ne structure intervals of the 2'I" state of helium to an accuracy of 1/10', we have undertaken a program of calculations which, it is hoped, will lead to a new determination of the 6ne-structure constant n. This paper gives a brief survey of the over-all program, and a detailed report of the successful completion of the', 6rs...

The helium fine-structure controversy

There is presently disagreement between theory and experiment as well as between different theoretical calculations concerning the fine-structure splitting of the lowest P state of the neutral helium atom. We believe that we have found a minor error in the formulas used by Drake et al. (Can. J. Phys. 80, 1195 (2002)) in their calculations, and we may have an explanation how the error has occurr...

Helium fine structure theory for determination of α

We present a recent progress in the calculation of helium fine-structure splitting of the 2PJ states, based on the quantum electrodynamic theory. Apart from the complete evaluation of mα and m/M α corrections, we have performed extensive tests by comparison with all experimental results for light helium-like ions and with the known large nuclear charge asymptotics of individual corrections. Our...

The Meaning of the Fine Structure Constant

Improved theory of helium fine structure.

Improved theoretical predictions for the fine-structure splitting of 2(3)PJ levels in helium are obtained by the calculation of contributions of order alpha5 Ry. New results for transition frequencies nu(01) = 29616943.01(17) kHz and nu(12) = 2291161.13(30) kHz disagree significantly with the experimental values, indicating an outstanding problem in bound state QED.