$\mathbf{\alpha}$-induced reaction cross sections in the mass range $\mathbf{A \approx 20 - 50}$: a critical review

TL;DR

This paper critically reviews alpha-induced reaction cross sections for nuclei with mass numbers approximately 20 to 50, analyzing trends, outliers, and new data, and discusses the relation between astrophysical energies and reduced energies.

Contribution

It provides a comprehensive review of cross section trends, identifies outliers, and introduces new data and a relation between effective astrophysical energy and reduced energy.

Findings

Most alpha-induced reaction cross sections follow a smooth trend.

Four outliers with anomalous cross sections were identified.

New data for $^{23}$Na align with general systematics.

Abstract

In a recent review it was shown that the cross sections of $\alpha$-induced reactions in the $A \approx 20 - 50$ mass range follow a general and smooth trend in most cases. For comparison of cross sections of different targets at various energies the method of reduced cross sections $\sigma_{\rm{red}}$ and reduced energies $E_{\rm{red}}$ was used. Four outliers were identified: $^{36}$Ar and $^{40}$Ar with unusally small cross sections and $^{23}$Na and $^{33}$S with unusually large cross sections. New data for $^{23}$Na were presented at this NPA-7 conference; contrary to the previous data, these new data fit into the general systematics. In addition, a relation between the most effective energy $E_0$ for astrophysical reaction rates (the so-called Gamow window) and the reduced energy $E_{\rm{red}}$ is presented.