Detector array for locating radioactive sources in three dimensions

A method for locating a radioactive source comprising:

• providing a two-dimensional array of detectors, each detector being configured to detect particles from the radioactive source and responsively emit signals, the detector array comprising frontward detectors interleaved with rearward detectors, wherein a front surface of each frontward detector is frontwardly offset relative to a front surface of each adjacent rearward detector;
• determining a frontward detection peak comprising a subset of the frontward detectors having enhanced detection of the particles;
• determining a rearward detection peak comprising a subset of the rearward detectors having enhanced detection of the particles;
• determining a width of the frontward detection peak;
• determining a width of the rearward detection peak;
• determining a position of the radioactive source by comparing the width of the frontward detection peak to the width of the rearward detection peak;
• and
• applying a predetermined distance correlation function that relates the distance of the radioactive source to the width of whichever detection peak, of the frontward and rearward detection peaks, has a smaller width.

A method for locating a radioactive source comprising:

• providing a two-dimensional array of detectors, each detector being configured to detect particles from the radioactive source and responsively emit signals, the detector array comprising frontward detectors interleaved with rearward detectors, wherein a front surface of each frontward detector is frontwardly offset relative to a front surface of each adjacent rearward detector;
• determining a frontward detection peak comprising a subset of the frontward detectors having enhanced detection of the particles;
• determining a rearward detection peak comprising a subset of the rearward detectors having enhanced detection of the particles;
• determining a width of the frontward detection peak;
• determining a width of the rearward detection peak;
• determining a position of the radioactive source by comparing the width of the frontward detection peak to the width of the rearward detection peak;
• and
• determining a distance correlation function that relates the distance of the radioactive source to the width of the frontward or rearward detection peak by placing a radioactive test source sequentially at a plurality of distances from the detector array and, at each distance of the plurality of distances, determining the width of the frontward or rearward detection peak respectively.