THE CR-50(ALPHA, N)FE-53 AND CR-50(ALPHA, P)MN-53 CROSS-SECTIONS

The cross sections of the reactions Cr-50(alpha, n)Fe-53 and Cr-50(alp ha, p)Mn-53 have been measured over bombarding-energy ranges of 5.409- 10.009 MeV and 4.868-10.009 MeV respectively. The data, together with those for Ti-48(alpha, n), (alpha, p) from a previous measurement, hav e been compared with the results of statistical-model calculations. Ne w prescriptions of optical-model parameters for use exclusively with N = 28 compound nucleus reactions are presented. Thermonuclear reaction rates for Cr-50(alpha, n), (alpha, p) have been calculated for temper atures appropriate for stellar nucleosynthesis, and have been compared with published rates derived from experimental measurements and stati stical-model calculations.