Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published March 5, 1979 | public
Journal Article

Cross section measurements and thermonuclear reaction rates for ^(48)Ca(p, γ)^(49)Sc and ^(48)Ca(p, n)^(48)Sc

Abstract

Absolute cross sections have been measured for the reaction ^(48)Ca(p, γ)^(49)Sc for 0.579 MeV ≦ Ep, lab ≦ 2.670 MeV and for the reaction ^(48)Ca(p, n)^(48)Sc for 0.956 MeV ≦ E_(p,lab) ≦ 2.670 MeV. Substantial competition effects in the cross section for ^(48)Ca(p, γ)^(49)Sc were observed at the thresholds for neutron emission to the 623 keV (3^+), 1143 keV (2^+) and 1402 keV (2^−) excited states of ^(48)Sc. Thermonuclear reaction rates were calculated from the measured cross sections for 0.1 ≦ T_9 ≦ 10.0. The new rates differ considerably from those used in earlier calculations of the production of the rare, neutron-rich intermediate mass nuclides during explosive carbon burning. In particular, the new rates may change the predicted abundances for ^(48)Ca, ^(49,50)Ti and ^(50)V substantially. The good agreement between current global Hauser-Feshbach models and the experimental data indicates that Hauser-Feshbach calculations can provide sufficiently reliable rates for astrophysical calculations in cases where experimental data are non-existent.

Additional Information

© 1979 North-Holland Publishing Co. Received 23 October 1978. Supported in part by the National Science Foundation [PHY76-83685]. Fannie and John Hertz Foundation Fellow, September 1973-December 1977. It is a pleasure to acknowledge many helpful discussions with Dr. D. G. Sargood and his valuable participation in the calibration of the BF_3 "long counter" which was used in the present work for neutron detection.

Additional details

Created:
September 15, 2023
Modified:
October 23, 2023