5 - Recent examples

Summary

In the preceding chapters the material necessary for studying photoionization processes in atoms using synchrotron radiation and electron spectrometry was presented. The discussion will now be completed with some examples of current research activities. These include:

1. photon-induced electron emission around the 4d ionization threshold in xenon from which a complete mapping of these spectra can be obtained and many features characteristic of inner- and outer-shell photoprocesses are well visualized;

2. a complete experiment for 2p photoionization in magnesium which also provides a detailed illustration of the role that many-electron effects have on main photolines;

3. an investigation of discrete satellite lines in the outer-shell photoelectron spectrum of argon which demonstrates for a simple case the origin of satellite processes in electron correlations, and also the importance that instrumental resolution has on the determination of satellite structures;

4. a complete experiment for 5p_3/2 photoionization in xenon which includes a measurement of the photoelectron's spin polarization;

5. a quantitative study of postcollision interaction (PCI) between 4d_5/2 photoelectrons and N₅–O_{2, 3}O_{2, 3}¹S₀ Auger electrons in xenon which also serves as an example of energy calibration in accurate experiments;

6. the determination of coincidences between 4d_5/2 photoelectrons and N₅–O_{2, 3}O_{2, 3}¹S₀ Auger electrons in xenon which allows a spatial view of the angular correlation pattern for this two-electron emission process;

7. a near-threshold study of state-dependent double photoionization in the 3p shell of argon in which the cross section approaches zero and two electrons of extremely low kinetic energy have to be measured in coincidence.