Posted on by maxfomitchev

CapeSym SrI2(Eu) scintillation detectors mounted on a silicon photomultiplier (SiPM) are characterized by high resolution and compact form factor.

In this blog post I am going to evaluate a CapeSym SC-14x2c-SiPM-T detector, which has a 14 x 2 mm SrI2(Eu) scintillation crystal mounted on a silicon photomultiplier – Fig. 1.

Fig. 1. CapeSym SrI2(Eu) SC-14x2c-SIPM-T detector.

The SC-14x2c-SiPM-T detector has a 0.5 mm thick beryllium window and is optimized for low-energy gamma ray detection. Still, high atomic weight of strontium makes this detector suitable for detecting gamma rays up to 1 MeV, although with significantly reduced efficiency.

The SC-14x2c-SiPM-T detector requires +30 V power applied to the anode pin, and the detector signal can be read from the cathode pin (50 Ohm). 3x 9V batteries can be used to power the detector – Fig. 2.

Fig. 2. Connectivity and power assembly for the SC-14x2c-SIPM-T detector.

137Cs spectrum is shown on Fig. 3. The spectrum was captured using the MCA-PRO running the PulseCounter software. The measured 661.7 keV peak width was 2.4% FWHM.

Fig. 3. 137Cs spectrum captured using the SC-14x2c-SIPM-T detector.

133Ba, 57Co, and 241Am spectra are shown on Fig. 4-6. Resolution at 59.5 keV is 7.5% FWHM.

Fig. 4. 133Ba spectrum captured using the SC-14x2c-SIPM-T detector.
Fig. 5. 57Co spectrum captured using the SC-14x2c-SIPM-T detector.
Fig. 6. 241Am spectrum captured using the SC-14x2c-SIPM-T detector.

55Fe spectrum is shown on Fig. 7. Although the resolution is not great (~40% FWHM) due to intrinsic and electronic noise, the main feature is that the 5.9 keV x-ray peak is discernable.

Fig. 7. 55Fe spectrum captured using the SC-14x2c-SIPM-T detector.

Conclusion

Priced just under $1,000 USD CapeSym SC-14x2c-SiPM-T detector is a very compact and high resolution device suitable for a wide range of gamma spectroscopy applications.