Enhanced Nuclear Binding Near the Proton Dripline Opens Possible Bypass of the $^{64}{\rm Ge}$ rp-process Waiting Point

Z. Meisel; W. -J. Ong; J. S. Randhawa

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arXiv · 2505.00143

Enhanced Nuclear Binding Near the Proton Dripline Opens Possible Bypass of the $^{64}{\rm Ge}$ rp-process Waiting Point

Z. Meisel·W. -J. Ong·J. S. Randhawa

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Abstract

We performed astrophysics model calculations with updated nuclear data to identify a possible bypass of the $^{64}{\rm Ge}$ waiting-point, a defining feature of the rapid-proton capture (rp-) process that powers type-I x-ray bursts on accreting neutron stars. We find that the rp-process flow through the $^{64}{\rm Ge}$ bypass could be up to 36\% for astrophysically relevant conditions. Our results call for new studies of $^{65}{\rm Se}$, including the nuclear mass, $\beta$-delayed proton emission branching, and nuclear structure as it pertains to the $^{64}{\rm As}(p,\gamma)$ reaction rate at x-ray burst temperatures.

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Z. Meisel, W. -J. Ong, J. S. Randhawa. 2025-04-30. Enhanced Nuclear Binding Near the Proton Dripline Opens Possible Bypass of the $^{64}{\rm Ge}$ rp-process Waiting Point. https://arxiv.org/abs/2505.00143

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