Copyright © 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024
Snakedance Scientific, LLC
A Radiological "Snakedance"
Shown here is a portion of a spectrum of mineral deposits in a pipe from a copper mine. The actual data can be seen as a "stair-step" histogram in light gray. Fitted decay chain shapes are in different colors corresponding to the colors of the text in the legend. The mineral deposits were shown to have significant concentrations of natural radionuclides, primarily radium, that were not in secular equilibrium. The spectrum was analyzed with VRF, our premier analysis program. The remarkable deconvolution of peaks is made possible by our technique of fitting each of many full-spectrum decay-chain shapes with non-linear least-squares rather than beginning with the results of a simple peak search as is done by traditional analysis programs.
Snakedance Scientific, LLC
Next-Generation Gamma Spectral Analysis with Full-Spectrum Non-Linear Least-Squares Fitting
Our goal is to make the full power of our new method of analysis of nuclear radiation spectra available at affordable prices with a user-friendly interface, which we call "VRF".
VRF is especially useful for analysis of difficult spectra with limited data and spectra with multiple sources having different attenuations and overlapping peaks. Instead of fitting each peak individually, as is done with other programs, VRF fits all of the data in the entire spectrum as a single, self-consistent function. X-rays from decay, escape peaks, and summing peaks are included. This makes VRF particularly adept at resolving spectral features composed of multiple peaks. At the core of VRF is a non-linear engine that optimizes the values of a large number of free variables until no better fit to the data can be found. While finding the best fit of each of many full-spectrum radiation source shapes, VRF simultaneously finds the best fit for detector efficiency, energy calibration, resolution calibration, the effects of attenuation on separate groups of radiation sources, and the effects of peak summing due to random or cascade coincidence.
VRF maintains an extensive library of 1192 radionuclides and has intuitive visually-driven tools for reporting, graphing, and specialized analysis. We continually improve VRF in response to suggestions from our user analysts, and updates to each major version are made available to all licensed users as they occur. Licenses to VRF are sold on this site at prices that are considerably lower than less-powerful traditional analysis programs that begin with simple peak searches.