A photoelectron-photoion coincidence method for the investigation of decay probabilities after innershell photoionization

The photoelectron-photoion method presented is shown to be very successful for the quantitative investigation of decay probabilities after innershell photoionization. Especially for the determination of K-shell fluorescence yields of light elements, where only scarce data exist up to now, this method opens up new ways. For all elements we present a general approach to determine fluorescence yields. As an example the investigation of the 1 s decay of free sodium atoms is presented