Radioactive anomaly discrimination from spectral ratios
First Claim
1. A method for discriminating a radioactive anomaly from naturally occurring radioactive materials, the method comprising:
- detecting a first number of gamma photons having energies for each of a first plurality of gamma energy lines within a predetermined period of time;
detecting a second number of gamma photons having energies for each of a second plurality of gamma energy lines within the predetermined period of time;
summing together the first numbers of gamma photons from each of the plurality of first gamma energy lines to obtain a first gamma photon total;
summing together the second numbers of gamma photons from each of the plurality of second gamma energy lines to obtain a second gamma photon total;
determining, in a controller, a ratio of the first gamma photon total and the second gamma photon total; and
determining that a radioactive anomaly is present when the ratio exceeds a threshold value.
1 Assignment
0 Petitions
Accused Products
Abstract
A method for discriminating a radioactive anomaly from naturally occurring radioactive materials includes detecting a first number of gamma photons having energies in a first range of energy values within a predetermined period of time and detecting a second number of gamma photons having energies in a second range of energy values within the predetermined period of time. The method further includes determining, in a controller, a ratio of the first number of gamma photons having energies in the first range and the second number of gamma photons having energies in the second range, and determining that a radioactive anomaly is present when the ratio exceeds a threshold value.
-
Citations
19 Claims
-
1. A method for discriminating a radioactive anomaly from naturally occurring radioactive materials, the method comprising:
-
detecting a first number of gamma photons having energies for each of a first plurality of gamma energy lines within a predetermined period of time; detecting a second number of gamma photons having energies for each of a second plurality of gamma energy lines within the predetermined period of time; summing together the first numbers of gamma photons from each of the plurality of first gamma energy lines to obtain a first gamma photon total; summing together the second numbers of gamma photons from each of the plurality of second gamma energy lines to obtain a second gamma photon total; determining, in a controller, a ratio of the first gamma photon total and the second gamma photon total; and determining that a radioactive anomaly is present when the ratio exceeds a threshold value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A method for determining the presence or absence of an expected radiation source, the method comprising:
-
placing at least one radioactive material detection apparatus on an object containing the expected radiation source; detecting, with the at least one radioactive material detection apparatus, a first number of gamma photons emitted by the expected radiation source having energies for each of a first plurality of gamma energy lines within a predetermined period of time; detecting, with the at least one radioactive material detection apparatus, a second number of gamma photons emitted by the expected radiation source having energies for each of a second plurality of gamma energy lines within the predetermined period of time; summing together the first numbers of gamma photons from each of the plurality of first gamma energy lines to obtain a first gamma photon total; summing together the second numbers of gamma photons from each of the plurality of second gamma energy lines to obtain a second gamma photon total; determining, in a controller, a ratio of the first gamma photon total an the second gamma photons photon total; and comparing the determined ratio of the first and second gamma photon total with an expected ratio of the first and second gamma photon total for the expected radiation source.
-
-
16. A system for discriminating a radioactive anomaly from naturally occurring radioactive materials, the system comprising:
-
at least one radioactive material detection apparatus configured to detect a first number of gamma photons having energies for each of a first plurality of gamma energy lines within a predetermined period of time and a second number of gamma photons having energies for each of a second plurality of gamma energy lines within the predetermined period of time; and a controller configured to; (i) determine a ratio of a sum total of the first number of gamma photons from each of the first plurality of gamma energy lines and a sum total of the second number of gamma photons from each of the second plurality of gamma energy lines, and (ii) compare the determined ratio with a threshold value. - View Dependent Claims (17, 18, 19)
-
Specification