{\rtf1\ansi\ansicpg1250\deff0\deflang1038\deflangfe1038\deftab708{\fonttbl{\f0\froman\fprq2\fcharset238{\*\fname Times New Roman;}Times New Roman CE;}} \viewkind4\uc1\pard\f0\fs24 Status of software for PGNAA bulk analysis by the Monte Carlo - Library Least-Squares (MCLLS) approach \par }

摘要: {\rtf1\ansi\ansicpg1250\deff0\deflang1038\deflangfe1038\deftab708{\fonttbl{\f0\froman\fprq2\fcharset238{\*\fname Times New Roman;}Times Roman CE;}} \viewkind4\uc1\pard\f0\fs24 The Center for Engineering Applications of Radioisotopes (CEAR) has been working about ten years on the Monte Carlo - Library Least-Squares (MCLLS) approach treating nonlinear inverse analysis problem PGNAA bulk analysis. This consists essentially using simulation to generate libraries all elements be analyzed plus any other required libraries. These are then used in linear (LLS) with unknown sample spectra analyze sample. include sources background which includes: (1) gamma-rays emitted by neutron source, (2) prompt produced analyzer construction materials, (3) natural from K-40 and uranium thorium decay chains, (4) NaI detector activation. A number unforeseen problems have arisen pursuing this including: activation most common (NaI) systems, nonlinearity detector, difficulties obtaining response functions (and other) detectors. addressed CEAR recently either solved or almost at present time. We now finished development except gamma-ray library detector. must first determine a treatment coincidence schemes Na particularly I complete last library. \par }