A multiwire proportional counter for XAS fluorescence experiments

A multiwire proportional counter was used in fluorescence X-ray absorption measurements and a comparison to a Si(Li) and NaI(Tl) detectors was done. The main features of the mutiwire proportional counter are its high counting rate capability (10⁷ counts s^-1) and large active area (6 × 6 cm²). It was shown that the MWPC is suitable for fluorescence absorption. Although the maximum capability was not reached in the present experiments, it was found that as the counting rate increase the MWPC performance became better than Si(Li) detectors and shows a similar response to the scintillator counter at medium counting rates (up to 10⁵ counts s^-1).