Patent ID: 9678228
Date: 2017-06-13
CPC Classifications: G01T

Claim:
1. A real-time cartography method of distribution of the presence of a source of photons in a ground, the method comprising steps of measuring, in a plurality of measuring points, a flow of photons in a determined energy band with a non-collimated spectrometric detector, and logging the geographic coordinates of said point, and in each measuring point, setting up a probability distribution of provenances of photon emitting source locations around a current measuring point, said setting up comprising the steps of: from an intrinsic efficacy of the spectrometric detector and a hypothesis on the distribution of radionuclides in the ground determining a distribution of the ratio of counting of photons emitted from each of the surrounding areas of the current measuring point over the total counting of photons detected at the current measuring point by the spectrometric detector, calculating the probability distribution of photon emitting source locations based on the ratio distribution with respect to the ground around the current measuring point, modelling the probability distribution on a surface, and representing the probability distribution of provenances of photons on a map of the ground, by projecting said surface onto the map of the ground, the method further comprising, for each measuring point from the second, a step performed prior to the representation step, during which the distributions of provenances of photons around the current measuring point are correlated with those of previous measuring points.