Working characteristics of gas flow proportional counter designed for X-ray Mossbauer spectrometry

Abstract

Thin proportional counter for scattering Mossbauer spectrometry (GEMS and XMS) was constructed and the working characteristics were studied to find the optimal condition for the effective detection of the resonant scattered X-ray. The variation of energy spectrum of scattered X-ray was analyzed as a function of the distance between γ-ray source and the sample and the distance between two wire anodes stretched parallel inthe detector. Although photo peaks of resonant X-ray reemitted from the sample surface did not appear clearly in the photon spectrum, the photo peak and escape peak due to resonantly reemitted X-ray and continuous X-ray were observed. The most strong resonant X-ray was found at energies lower than that of Fe X-ray. With the newly designed proportional counter, scattering Mossbauer spectra of iron+silicon (3%) steel and chromium coated steel were measured and the magnetism and chemical composition of the steel surface layers were analyzed.