Calibration software EffMaker
EffMaker software package has been developed for calculation of detection efficiency and modeling of gamma-spectra in different measuring geometries using Monte-Carlo method. EffMaker can be used for measurements of objects activity by gamma-spectrometric methods when the spectrometer calibration can be hardly done by reference standards, e.g. for measurements of transport containers, packages with radioactive wastes, others wastes. Objects with arbitrary distribution of activity, which includes nonuniform distribution, can be modeled using this software package. So it can be used for analysis of how radionuclides distribution in the sample affects the activity measurements results. This function presents the promising way of EffMaker using for development and testing of software and methodological support.
A modeled object is a dissymmetric structure consisting of embedded cylinders, parallelepipeds, spheres. So objects with sophisticated parameters and arbitrary distribution of activity can be modeled: with surface (internal and external), volume distribution etc.
The built-in set of patterns in EffMaker simplifies the creation of complex geometrical objects with nonuniform activity distribution. The following patterns are included:
- a truncated cone, with one-layer or two-layer walls;
- an empty or filled tube, open sidelong test tube with internal or external surface contamination;
- cylinder, profile, top or bottom view, with one layer of the source;
- a box for the air tubes modeling with external contamination, activity can be distributed in internal or external layers;
- spherical objects with internal contamination like pipe closers;
- angle bar and double tee with random orientation, with the contaminated surface;
- circular and rectangular plates.
- fine adjustment of relative position of the detector and the object, including the option of the detector placing inside the object;
- calculation of spectrum and detection efficiency for the selected geometry;
- batch calculation of detection efficiency for different detectors and objects;
- energy spectrum calculation using energy grid or by setting of activities of radionuclides taking into account the decay chain;
- radionuclides database on the basis of ENSDF compatible with Nuclide Master;
- the database of cross-sections of interaction of gamma rays with matter for setting of arbitrary material of the object;
- the database with models and calculation results;
- integration of calculation results with SpectraLine software package.
The response function is modeled for the detector to the increase of the calculations speed. This function is a set of spectra for monochromatic radiation in the prescribed range. The response function is transformed to the response matrix which takes into account number of channels of the spectrometer and its resolution. The gamma spectrum of the object (the physical spectrum of the source) in the point of the detector’s location is modeled independently. The detector spectrum of the source is obtained as a convolution of the physical spectrum with the detector’s response matrix.