R-matrix studies of astrophysical capture reactions

Johnson, A. S.; Hale, G. M.
July 2000
AIP Conference Proceedings;2000, Vol. 529 Issue 1, p466
Academic Journal
We report the recent results of R-matrix analyses of light systems directed at obtaining capture cross sections for reactions of interest in nuclear astrophysics. The two examples discussed are [sup 1]H(n,γ)[sup 2]H and [sup 12]C(α,γ)[sup 16]O. The first reaction is important in Big-Bang nucleosynthesis at energies well up into hundreds of keV. The second reaction is crucial for determining the relative abundances of carbon and oxygen at the end of the helium-burning phase, but at energies below the range of current measurements. In both cases, the direct measurements are rather sparse and sometimes difficult to interpret because of level-structure uncertainties. However, the analyses we will describe make use of auxiliary data to determine the cross sections over wide ranges of energies, including those of astrophysical interest. © 2000 American Institute of Physics.


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