CPC G01N 23/204 (2013.01) [G01N 23/20083 (2013.01); G01T 3/00 (2013.01); G01T 3/06 (2013.01); G01V 5/0091 (2013.01)] | 10 Claims |
1. A method for identifying a radioactive source comprising the steps of:
a) detecting, using a gamma spectroscopic Type I detector, gamma emitting sources of said radioactive source;
b) detecting, using a gamma/neutron Type II detector, a plurality of impulses of said radioactive source, said plurality of impulses being associated with respective neutron emissions and gamma emissions;
c) identifying a first portion of said plurality of impulses associated with respective neutron emissions and a second portion of said plurality of impulses associated with respective gamma emissions, said step of identifying said first portion and said second portion of impulses including a calculation for each impulse of a respective total integral Ltot of the impulse, and further comprising the steps of:
d) determining a first number nn of impulses belonging to the first portion of said plurality of impulses and a second number nγ of impulses belonging to the second portion of said plurality of impulses;
e) calculating a first average value En and a second average value Eγ of the total integral Ltot, wherein En=ΣNn (Ltot/nn), and Eγ=Σnγ (Ltot/nγ);
f) calculating datum parx=nγ/nn and datum pary=Eγ/En;
g) identifying if the radioactive source belongs to a first group of neutron sources or to a second group of gammas sources by the data parx, pary;
h) if in step (g), the radioactive source belongs to the first group of neutron sources, identifying gamma sources detected with the first group of neutron sources using the Type I detector, through spectroscopy;
i) double confirming identification of the radioactive source of step (g) if both gamma and neutron sources are detected;
j) detecting a masking condition of neutrons in presence of gamma emissions, performed by merging results of the identification from the Type I detector with the results of the identification from the Type II detector; and
k) detecting and identifying gamma and neutron sources in presence of moderators and/or shielding materials through the Type II detector.
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