Patent ID: 8513601

Claim:
A particle detection system, comprising: a first set of position sensitive charged particle detectors located on a first side of an object holding area to measure positions and directions of incident charged particles towards the object holding area; a second set of position sensitive charged particle detectors located on a second side of the object holding area opposite to the first side to measure positions and directions of outgoing charged particles exiting the object holding area; means for processing scattering of the charged particles in the materials within the object holding area based on the measured incoming and outgoing positions and directions of charged particles to obtain a tomographic profile or the spatial distribution of scattering centers within the object holding area, means for reconstructing a trajectory of a charged particle through the object holding area; means for measuring a momentum of an incoming charged particle based on signals from the first set of position sensitive charged particle detectors; means for measuring a momentum of an outgoing charged particle based on signals from the second set of position sensitive charged particle detectors; means for obtaining a spatial distribution of a scattering density of the object holding area, means for determining spatial distribution of the scattering density of the object holding area to obtain predetermined charged particle tomography data corresponding to scattering angles and estimated momentum of charged particles passing through the object holding area; means for producing a probability distribution of charged particle scattering for use in an expectation maximization algorithm based on a statistical multiple scattering model; and means for determining a substantially maximum likelihood estimate of the scattering density of the object holding area using the expectation maximization algorithm, wherein the first set of position sensitive charged particle detectors includes a first double-layer of drift tubes arranged in an X direction and a second double-layer of drift tubes arranged in a Y direction.