High-precision mass measurement of $^{24}$Si and a refined determination of the $rp$ process at the $A=22$ waiting point

TL;DR

This study provides a highly precise mass measurement of $^{24}$Si, significantly improving the accuracy of the $rp$ process modeling in X-ray bursts by refining the reaction rate at the $A=22$ waiting point.

Contribution

The paper presents a high-precision mass measurement of $^{24}$Si, reducing the uncertainty in the $rp$ process reaction rate and constraining the onset temperature of the $( extalpha,p)$ process.

Findings

Mass excess of $^{24}$Si measured with 5 times higher precision.

Reaction rate uncertainty reduced, improving $rp$ process models.

Onset temperature of the $( extalpha,p)$ process constrained to 9%.

Abstract

We report a high precision mass measurement of $^{24}{\rm Si}$, performed with the LEBIT facility at the National Superconducting Cyclotron Laboratory. The atomic mass excess, $10\;753.8$(37) keV, is a factor of 5 more precise than previous results. This substantially reduces the uncertainty of the $^{23}{\rm Al}(p,\gamma)^{24}{\rm Si}$ reaction rate, which is a key part of the rapid proton capture ($rp$) process powering Type I X-ray bursts. The updated rate constrains the onset temperature of the $(\alpha,p)$ process at the $^{22}{\rm Mg}$ waiting-point to a precision of 9%.