Determining soil contamination profiles from intensities of capture-gamma rays using above-surface neutron sources (vol 50, pg 415, 1999)

Four methods are presented to estimate contaminant concentration profiles i n soil from the intensities of neutron-induced capture-gamma photon intensi ties measured at the soil surface. In particular, the method of linear regu larization with and without an iterative positivity constraint, the Backus- Gilbert method, and the maximum entropy method are applied to the soil cont amination problem. Example results obtained with the four methods are given for photon intensities calculated for idealized test contaminant profiles in soil irradiated by neutron sources above the surface. (C) 2001 Elsevier Science Ltd. All rights reserved.