NEAR THRESHOLD 4D PHOTOEXCITATION AND PHOTOIONIZATION OF XE

The angular distribution parameter beta of the N5-O2,3O2,3 Auger lines has been measured between the 4d5/2 and the 4d3/2 thresholds of Xe using the cis technique. The radiationless decay parameter alpha2 for each of the N5-O2,3O2,3 Auger lines and the alignment parameter A20 for the intermediate ion were also determined. Comparisons with previous values of beta and alpha2 for the N5-O2,3O2,3 Auger lines have been made. In addition, shakeoff to the various states of the Xe2+ 5p4 ion has been measured following 4d photoexcitation and found to be small. These results support the contention that near-zero kinetic energy electrons observed following similar photoexcitation in the rare gases result primarily from a two-step process rather than the direct process of shakeoff.