학술논문
First direct measurement constraining the $^{34}$Ar($\alpha$,p)$^{37}$K reaction cross section for mixed hydrogen and helium burning in accreting neutron stars
Document Type
Working Paper
Author
Browne, J.; Chipps, K. A.; Schmidt, K.; Schatz, H.; Ahn, S.; Pain, S. D.; Montes, F.; Ong, W. J.; Greife, U.; Allen, J.; Bardayan, D. W.; Blackmon, J. C.; Blankstein, D.; Cha, S.; Chae, K. Y.; Febbraro, M.; Hall, M. R.; Jones, K. L.; Kontos, A.; Meisel, Z.; O'Malley, P. D.; Schmitt, K. T.; Smith, K.; Smith, M. S.; Thompson, P.; Toomey, R.; Vostinar, M.; Walter, D.
Source
Phys. Rev. Lett. 130 (2023) 212701
Subject
Language
Abstract
The rate of the final step in the astrophysical $\alpha$p-process, the $^{34}$Ar($\alpha$,\textit{p})$^{37}$K reaction, suffers from large uncertainties due to lack of experimental data, despite having a considerable impact on the observable light curves of x-ray bursts and the composition of the ashes of hydrogen and helium burning on accreting neutron stars. We present the first direct measurement constraining the $^{34}$Ar($\alpha$,p)$^{37}$K reaction cross section, using the Jet Experiments in Nuclear Structure and Astrophysics (JENSA) gas jet target. The combined cross section for the $^{34}$Ar,Cl($\alpha$,p)$^{37}$K,Ar reaction is found to agree well with Hauser-Feshbach predictions. The $^{34}$Ar($\alpha$,2p)$^{36}$Ar cross section, which can be exclusively attributed to the $^{34}$Ar beam component, also agrees to within the typical uncertainties quoted for statistical models. This indicates the applicability of the statistical model for predicting astrophysical ($\alpha$,p) reaction rates in this part of the $\alpha$p process, in contrast to earlier findings from indirect reaction studies indicating orders-of-magnitude discrepancies. This removes a significant uncertainty in models of hydrogen and helium burning on accreting neutron stars.
Comment: 6 pages, 4 figures
Comment: 6 pages, 4 figures