Patent ID: 7897932

Claim:
A radioisotope identification device comprising: a gamma-ray detector having three dimensional vertex localization; said gamma-ray detector producing a first three dimensional vertex localization and a second three dimensional vertex localization corresponding to two interaction locations resulting from one incident gamma-ray event; said gamma-ray detector having a first deposited energy output for each said gamma-ray event; wherein said gamma-ray detector is configured to produce an event datum containing said first deposited energy output, said first three dimensional vertex localization and said second three dimensional vertex localization for each gamma-ray event; a computer-readable storage media, wherein a data set of emission gamma-ray energies characteristic of suspect radioisotopes is stored on said computer-readable storage media; a system controller comprising a processor wherein said system controller is communicatively coupled to said gamma-ray detector; a computational processor communicatively coupled to said computer-readable storage media; wherein said computational processor is configured to select a first event datum and a second event datum; wherein said computational processor is configured to select a first hypothetical emission gamma-ray energy for said first event datum and to select a second hypothetical emission gamma-ray energy for said second event datum; wherein said computational processor is configured to calculate first backprojection data using value of said first hypothetical emission gamma-ray energy and value of said first deposited energy output, said first three dimensional vertex localization and said second three dimensional vertex localization for said first event datum and to calculate second backprojection data using value of said second hypothetical emission gamma-ray energy and value of said first deposited energy output, said first three dimensional vertex localization and said second three dimensional vertex localization for said second event datum; wherein said computational processor is configured to calculate directional correlation between said first backprojection data for said first event datum and said second backprojection data for said second event datum; and an output from said computational processor indicating presence of radioisotope.