Deconvolution of Aerial Gamma Radiation Data (MSTS product number, DOE/NV/03624--0833)

Abstract:

Current aerial gamma radiation measurement analysis methods are significantly limiting in that they often operate on point‐wise on data to project signal to the ground. This approach ignores the large amount of correlation present between nearby measurements, and these methods derive significantly less information from the measurements than what is theoretically possible. We propose exploration of a rigorous computational physics based model for interpreting radiological measurements collected at altitude. Our method borrows from a simplified construct utilized in astronomy to sharpen images taken of deep space, in which the negative effects of blurring, atmospheric degradation, and optics aberrations are removed in order to sharpen images [1]. In our implementation, we seek to find the space and energy dependent photon emission density along ground level that is most consistent with the detector response observed from a collection of spectra measured at altitude above the terrain in question. No closed form solution exists for this inverse transport problem. Instead a 4‐D (space and energy) deconvolution problem must be solved via an iterative optimization procedure and appropriate forward model operator. The first impediment to solution is the known computational complexity of the forward operator (particle transport and detector response), the current research focuses on the underlying discretization and inversions processes to improve resolution of aerial gamma radiation measurements.

This work was done by Mission Support and Test Services, LLC, under Contract No. DE-NA0003624 with the U.S. Department of Energy and supported by the Site-Directed Research and Development Program. DOE/NV/03624—0833.

1. Starck & Pantin, Deconvolution in Astronomy: A Review, Publications of the Astronomical Society of the Pacific, October 2002.