The energy values of the individual members of those spin doublets of levels for certain atomic number ranges, for which only the experimentally obtained weighted averages of these energies were tabulated by Bearden and Burr (1967), have been calculated by using the screening parameters sigma 1 and sigma 2 previously reported by the authors. The energy values so obtained are further refined by the method of the modified Moseley plot. These refined energy values of the individual members of the spin doublets agree very well with the experimental electron spectroscopic energy values of Fuggle and Martensson (1980) and those of Cardona and Ley (1978) as corrected by Williams. The screening parameters sigma 1 and sigma 2 for a number of doublets of levels are reported for the first time.

It is well known that the Sommerfeld screening parameters U , and u2 for a spin doublet of levels can only be calculated if the individual energies of the two members of the doublet are known. In several cases, the resolution of the experimental method for finding the energies has proved insufficient and so only the energy of the unresolved doublet of levels has been reported. A new method has been developed for calculating these parameters for a spin doublet of levels by using the unresolved experimental energy values given by Bearden and Burr. The results of our calculations are presented. It is found that the energy values calculated by using these parameters in the Sommerfeld energy expression are in very good agreement with the recently reported resolved experimental energy values of the individual components of different spin doublets.

Using the recent theoretical atomic energy values of Huang et al. (1976), the values of the Sommerfeld screening parameter sigma 2 have been calculated for those spin doublet levels where calculations could not formerly be performed owing to the lack of experimental energy values. The method used was described earlier by Burr and Carson (1974) and involves no errors arising from the truncation of the series expansion of the Sommerfeld-Dirac relativistic energy expression. It is found that: (i) sigma 2 is a function of Z for all the spin doublets studied; (ii) the sigma 2 values calculated smoothly fit in the gaps in the sigma 2 against Z curves drawn by Burr and Carson; (iii) the sigma 2 values which show excessive scattering in the sigma 2 against Z curves drawn by Burr and Carson have been recalculated and are found to fit much better in the sigma 2 against Z curves; (iv) there exists a dip in the sigma 2 values in the regions of inner-shell filling (3d,4d, 4f,5d etc.) for all the doublets studied; (v) the sigma 2 values become negative for Z=22-25 (3d filling region) for the M2M3 spin doublet; and (vi) comparison of the sigma 2 against Z curves obtained by using the experimental energy values on the one hand, and the Huang et al. theoretical energy values on the other hand shows that the dips are quite pronounced in the latter case.

The source of solar energy is such a nuclear process in which hydrogen nuclei fuse together to form Helium nucleus. In this process, energy is released along with positrons and neutrino. Scientists have absorbed and counted these neutrons thereby revealing many hidden mysteries of the universe and fundamental particles. Research work done in the field of Neutrino Astronomy has given information about three states of neutrino.