Figure 2. Background Spectra at different positions
In figure 2, due to the statistical fluctuation, the total counts of
each spectrum were fluctuating. Except for outliers, the range of the
counts of each spectrum were about 30-62.
Spectrum investigation of signals containing radioactive
sources
For further investigation, we carried out the research of the spectra
containing radioactive sources. In the study, a Cs-137 source with
activity of 25kBq was employed.
According to the activity of the source, we set up several test
positions. The distances between source and test positions were
10cm,15cm,20cm,25cm,30cm and 35cm respectively. The dose rate
generated by the source at the test positions were
0.213μGy/h,0.095μGy/h,0.053μGy/h,0.034μGy/h,0.024μGy/h,and
0.017μGy/h. 100 sets of 1-s spectra were collected at each position. The
mean spectra at different test position and the total count of each
spectrum were shown in figure 3 and figure 4 respectively.