A substantial difference in the angular distributions of $2p$ photoelectrons from polarized oxygen atoms was found for two antiparallel atomic polarizations. This magnetic dichroism was studied as a function of photon energy from 25 to 52 eV. Our method extends traditional photoelectron angular distribution measurements of open shell atoms to “complete” experiments in similar to spin-resolved measurements. The observed dichroism allows a determination of the dipole matrix elements for the $\epsilon s$ and $\epsilon d$ photoelectrons and their phase difference including the sign.

• Received 21 May 1996

DOI:https://doi.org/10.1103/PhysRevLett.77.2642