Radioactive isotope identification

A method of identifying radioactive components in a source, the method comprising:

• (a) obtaining a gamma-ray spectrum from the source;
• (b) using at least one processor to identify peaks in the gamma-ray spectrum;
• (c) using said at least one processor to determine an array of peak energies and peak intensities from the identified peaks;
• (d) using said at least one processor to identify an initial source component based on a comparison of the peak energies with a database of spectral data for radioactive isotopes of interest, the spectral data comprising energies, relative intensities and classification information for emission lines association with radioactive isotopes of interest, wherein the emission lines are classified according to a predetermined significance according to their ability to identify the radioactive isotope with which they are associated;
• (e) using said at least one processor to estimate a contribution of the initial source component to the peak intensities;
• (f) using said at least one processor to modify the array of peak energies and peak intensities by subtracting the estimated contribution of the initial source component;
• and
• (g) using said at least one processor to identify a further source component based on a comparison of the modified array of peak energies with the database of spectral data.