Electronic Journal of Differential Equations,
Conference 04 (2000), pp. 37-50.

Title: The measurable distinction between the spin and orbital 
angular momenta of electromagnetic radiation

Authors: James H. Crichton (Seattle Pacific Univ., Seattle, Washington, USA)
 Philip L. Marston (Washington State Univ., Pullman, Washington, USA)
 
Abstract: 
We show how the angular momentum of electromagnetic radiation 
may be decomposed into spin and orbital parts, of which the 
spin part is measurable in terms of Stokes parameters, 
thereby providing an unambiguous, gauge-invariant, distinction 
between the two parts.

Published July 12, 2000.
Math Subject Classifications: 78A40, 78A46, 78A45, 81U40.
Key Words: Electromagnetic Radiation; Scattering; Angular Momenta.