Abstract
An area detector system for a wavelength-dispersive crystal spectrometer has been constructed for rapid chemical state analysis by external beam PIXE. Five position-sensitive proportional counters (PSPCs) are stacked and operated as a 2D detector. Each PSPC has a carbon fiber resistive anode. Pulses from the five PSPCs are converted into digital signals with a 512×5 channel charge-division analyzer. Five spectra are simultaneously obtained. A software converts this 2D data set into one spectrum after adjusting the offset channels. The spatial resolution of this system is somewhat larger than that of our single PSPC system previously developed. However the counting efficiency is five times higher than that of the single one.
Chemical state analysis in atmospheric air within several seconds to several minutes has been realized. Usefulness of this system for time-resolved chemical state analysis was demonstrated by measuring sulfur Kα spectra from a marine sediment sample.
