Toroidal proportional gas flow counter for conversion X-ray Mössbauer spectroscopy

This paper presents a new prototype of a toroidal proportional gas flow counter. This detector has been developed to be used in the Mössbauer spectroscopy for characterizing the surfaces of the iron bearing samples. The presented proportional counter allows to register both conversion X-rays (6.4 keV) and the backscattered gamma rays (14.4 keV) in the almost 2π geometry with the sufficient efficiency. This paper demonstrates the structure description of the detector and the optimization process of its use in the backscattering Mössbauer spectroscopy. The energy resolution of the detector is presented via the series of the multichannel analyses with different filters, where both energy peaks (6.4 keV and 14.4 keV) were observed. The measured Mössbauer spectra confirm the regularity of the energy assignment. The utilization of the aluminum filter enables to achieve a higher resonance effect, whereas the backscattered Mössbauer spectra were measured. The detector could be also used to measure in the transmission geometry with high efficiency.