Cylindrical scintillation proportional counter with WLS fiber readout

Characteristics of a scintillation proportional counter with wavelength-shifting (WLS) fiber optics readout for low energy deposition of 0.2-100 keV is described. The energy resolution of detector is 13% at 13.9 keV. The possibility of the detection of the proportional scintillation signal produced by the single electron of primary ionization is shown. A HV circuit and spectrometric electronics are totally separated form each other, that eliminates any technical problems of electronics damaging caused with a breakdown. There is no microphonic noise absolutely even for the large size counter. It can be utilized in areas with high vibration or with the strong influence of the electromagnetic field. This low threshold counter can be applied for the experiments in low-background physics and X-ray astronomy. With such a design the detector having large sizes and sensitive area with a fairly well uniformity is possible