Messungen zu den Vibrations- und Zweiquasiteilchenzuständen in172Yb

The Coster-Kronig and Auger spectrum of theL ₁ shell of gaseous argon has been investigated with an electrostatical spectrometer. The ionization in theL ₁ shell of argon was caused by electron impact. Absolute energies and relative intensities of all the Coster-Kronig and Auger transitions have been determined. The relative intensities of transitions within the groupsL ₁ L _{2, 3} M ₁,L ₁ L _{2, 3} M _{2, 3} andL ₁ MM agree fairly well with the theoretical values, calculated byRubenstein for extreme Russel-Saunders coupling, if intermediate coupling theory is used properly. Via the widthγ(L ₁) of theL ₁ level of argon, found in this experiment to be (1.84±0.2) eV, the following absolute group transition probabilities were determined (in units of 10¹⁴ sec^?1):W(L₁ L _{2, 3} M ₁)=(5.5±1.0),W(L₁ L _{2, 3} M _{2, 3})=(20.8±2.8),W(L₁ MM)=(1.44±0.16). The theoretical values are 21.0, 20.4 and 1.27. The possible reason for the large discrepancy between the experimental and theoretical value ofW(L₁ L _{2, 3} M ₁) is the use of the incorrect value of 287 eV for the binding energyE(L₁) byRubenstein. From the energies of theL ₁ MM transitions this value has been determined to beE(L₁)=(326.5±0.5) eV. This is the first direct measurement ofE(L₁) of argon.