The performance determination of a Compton-suppression spectrometer and the measurement of the low level radioactive Samples

• The performance of a Compton-suppression spectrometer (CSS) was determined.
• Aerosol samples collected after the Fukushima accident were measured by CSS.
• The activity concentrations of fission product were determined in the aerosol samples.

The performance of a new Compton-suppression spectrometer consisting of one HPGe detector and three NaI(Tl) detectors was studied. The peak-to-Compton ratio for a 137Cs source is 1150 and the integral background count rate is 0.3 5 s−1 over the energy interval 20–3000 keV. The spectrometer was used to acquire both Compton-suppressed and non-suppressed spectra of aerosol samples collected in Beijing following the Fukushima nuclear accident.