CROSS-SECTIONS FOR RADIATIVE-CAPTURE OF NEUTRONS BY OS-186, OS-187 UNDER STELLAR CONDITIONS

The cross sections for radiative capture of neutrons by Os-186, Os-187 in the energy interval 1-150 keV have been determined through an analysis of experimental data on the neutron cross sections of these nuclei under stellar conditions. Capture from excited states is taken into account. Mean stellar temperatures [kT] = 20-40 keV are considered. For [kT] = 30 keV the total capture cross sections are [sigma(gamma))st = 0.414 +/- 0.021 and 1.076 +/- 0.045 b for Os-186, Os-187, respectively. The possible systematic errors in the calculations are less than or similar to 2%.