Abstract
Many nuclear reactions of astrophysical importance are modeled by Hauser-Feshbach calculations, the well-established approach for computing average cross sections when many resonant levels are involved. This approach assumes that the density of levels is sufficient that only average properties, such as optical potentials and level densities, are sufficient to model the reaction. However, for intermediate masses or near the drip lines, these assumptions may break down. We have performed Monte Carlo simulations of the reaction cross section in order to assess the statistical error in the cross section or reaction rate prediction arising from the low density of states. The case of the 34Ar(α, p)37K reaction, which is an important reaction in x-ray bursts, is used as an example.
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Acknowledgements
It is a pleasure to thank K.A. Chipps, S.M. Grimes, M.A.A. Mamun, T. Rauscher, K. Schmidt, and A. Voinov for providing useful discussions and information. This work was supported in part by the U.S. Department of Energy, under Grants No. DE-FG02-88ER40387, DE-NA0002905, and DE-NA0003883.
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Brune, C.R. (2021). The Transition from Isolated Resonances to the Continuum. In: Escher, J., et al. Compound-Nuclear Reactions . Springer Proceedings in Physics, vol 254. Springer, Cham. https://doi.org/10.1007/978-3-030-58082-7_5
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