The library of evaluated and experimental data on the reactions of charged particle interaction with light nuclei
The library of nuclear data on interaction cross sections of charged particles with light nuclei z<10 (SaBa) was developed in the Russian Federal Nuclear Center -VNIIEF (Sarov) and contains complete information of this type both experimental and evaluated.
SaBa was prepared on the base of a handbook "Nuclear Physics Constants for Thermonuclear Fusion" //INDC(CCP)-326/L+F, VIENNA, 1991. The first version of the library was completed in 1999 and this year it was presented to IAEA for free distribution.
In the course of SaBa development extensive experimental information was collected and systematized: numerical and graphic data on cross sections of nuclear interactions. Evaluation techniques based on experimental data set fitting by spline-functions were created. Experimental data in some cases were supplemented by calculated and theoretical ones based on phase analysis of few-nucleon systems, analytical Gamov’s formula in the region of low energies, results of optical model calculation of elastic scattering, method of distorted wave Born approximation and the theory of resonance reaction.
The SaBa database is a program product including the library of evaluated and experimental data itself as well as a set of procedures making it possible to perform the sufficient processing of data.
Together with the factografic data specifying nuclear reactions the description of reactions in a text form is presented as well. This description in fact is a help system relating to all isotopes and reactions given in SaBa. Generally it includes a brief description of articles which were used to obtain an evaluated curve. Conditions of reaction run are specified. Authors present the description of their own evaluation techniques with a detailed analysis of the curve behavior in different energy ranges.
Currently the data on 86 reactions are presented in the base. The SaBa database presents the user the possibility to work in the mode of data preview, evaluated data obtaining and also in the mode of new data edit and input into the library.
All the modes of data processing are grouped in the appropriate blocks: LIBRARY, PROCESSING, EDITING. In this version of SaBa experimental data are presented in the form of tables of total cross-sections depending on energy, or coefficients of Legendre polynomials depending on energy.
At approximating the excitation functions of evaluated integral cross section the approximation function including generally a sum of resonance part and a background was used. The background is approximated by splines. The resonance part RI represents a sum of peaks and probably its own background in a polynomial form. To describe resonances Breit-Wigner formula is used.
Evaluated data are obtained using the maximum likelihood method in terms of systematic and random errors.
Together with data presentation in a form of cross section the presentation in a form of S-factor is widely used in the SaBa library as well. Besides the total cross section data and angular distributions the Saba library includes a large scope of data on reaction rates. User has a possibility to calculate the values of reaction rates in a given temperature range with the required accuracy.