Praga3 Radiometrics provides an advanced solution for the mapping and processing of airborne and ground gamma-ray spectrometry data acquired by modern spectrometers using NaI(Tl) detectors.
This feature-rich, GUI-oriented software was specifically developed to perform whole spectrum gamma-ray data processing. The use of whole-spectrum information is consistent with the latest developments in the theory and instrumentation of gamma-ray spectrometry. The full-spectrum technique includes a complete system of spectrum background removal. Aircraft, cosmic and radon background components can be separately adjusted by the user with the control of experimental calibration constants.
The integration of Praga3 within Oasis montaj™ provides geoscientists with a complete solution, and a seamless workflow for principle component analysis and advanced full-spectrum processing.
Window based processing
Praga3 Radiometrics provides window based processing functionality for: background removal, stripping, live-time, altitude and sensitivity corrections. The user is required to enter correct experimental calibration constants for the actual project using a dedicated program dialog. Processing methodology adheres to industry standards recommended by the IAEA.
Advanced Full-Spectrum Processing
The software’s full-spectrum processing was specifically designed for the processing of man-made (artificial) radiation data. It uses weighted least-squares fitting algorithm to find contributions of individual radionuclides into input spectra.The Praga3 technique uses model detector responses derived by the Monte Carlo photon transport simulation code.
Higher order components can be explained as mixed nuclide responses collected at average survey altitude. They are followed by components that account for the altitude changes.The remaining components contain statistical and instrumental noise.
Principal components can be used for gamma-ray data processing. The approach is very similar to the spectrum fitting technique. However, instead of model responses, a subset of spectrum components, derived directly from data, is used to replace the input spectrum.
Using Praga3 Radiometrics, the eigenvalue plot can be displayed. Users can browse through the individual components (eigenvectors) to investigate their shape. Covariance matrices can be displayed as well. Spectra can be interactively composed from the selected number of components and compared with input spectra or alternatively, residual spectra can be displayed. Once the eigenvectors are computed, there is no need to compute them again, for subsequent re-processing of data with another subset of components.
Praga3 Radiometric’s GUI oriented software enables analysis and interactive control of the dataset prior to the final processing. Using the spectrum browser, spectra can be investigated on spectrum-by-spectrum basis, and the proper function of the spectrum-fitting or principal component process can be assessed. Spectra displayed can be saved in an ASCII file.
Actual processing is done using a special processing mode where the spectrum display is disabled to speed up processing tasks. All tasks needed for a given project including standard window, full spectrum fitting, principal component analysis and processing can be done within the single processing run. Data output has range of options, there is a choice of relative (window count rate) or absolute (activity, exposure and dose rates) units for all, window, spectrum-fitting and principal component/ window techniques. In addition, results can be multiplied and offset by user defined constants if it is required. Output is currently provided in the form of ASCII delimited files.
- Spectrum browser with tools for peak identification,
- Window (ROI) based processing following IAEA standards,
- Advanced full-spectrum processing using leastsquares fitting technique,
- Principal component (NASVD or MNF) analysis and spectrum processing,
- Advanced support for radon removal including extended spectral-ratio and full-spectrum techniques.
*The Pico-Radiation-Air-to-Ground-Algorithm (PRAGA3) software was developed by Pico Envirotec and Spectronica. Geosoft licenses Praga3 Radiometrics as a montaj plus™ extension to Oasis montaj.