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 are described. The energy resolution of the detector is 13% at 13.9 keV. The possibility of detection of the proportional scintillation signal produced by a single electron of primary ionization is shown. The high voltage (HV) circuit and spectrometric electronics are totally separated from each other, to eliminate any technical problems from electronic components being damaged by a breakdown. There is no noise caused by a microphonic effect even for the large size counter. It can be utilized in areas with high vibration or under the strong influence of an electromagnetic field. This low threshold counter can be used for the experiments in low-background physics and X-ray astronomy. With such a design, a detector having large sizes and sensitive area with good uniformity is possible.