Experimental study of the relative probability of high-spin isomeric states population in ($\alpha$,n)-reactions

TL;DR

This study investigates the production of high-spin and low-spin isomers in alpha-induced nuclear reactions, revealing anomalous ratios and unique behaviors that enhance understanding of nuclear reaction mechanisms.

Contribution

It provides new experimental data on isomeric cross-section ratios in multiple reactions and analyzes the accuracy of computer models in describing these dynamics.

Findings

Confirmed anomalous isomeric cross-section ratios in $^{41}$K($ extalpha$,n)$^{44}$Sc.

Obtained unusually large isomeric ratios in $^{86}$Sr($ extalpha$,n)$^{89}$Zr and $^{112}$Sn($ extalpha$,n)$^{115}$Te.

Identified features of the $^{134}$Ba($ extalpha$,n)$^{137}$Ce reaction promising for fundamental research.

Abstract

Results of the investigations of the yield of high-spin and low-spin isomers in reactions $^{41}$K($\alpha $,n)$^{44}$Sc, $^{86}$Sr ($\alpha $,n)$^{89}$Zr, $^{112}$Sn($\alpha$,n)$^{115}$Te, and $^{134}$Ba($\alpha$,n)$^{137}$Ce in the energy range of the alpha particles 15 $\div$ 31 MeV based on off-beam measurements of induced activity of members of the isomeric pair are presented. The anomalous behavior of the isomeric cross-section ratios for the first of these reactions is confirmed. Uniquely large isomeric cross-section ratios for the second and third ones are obtained. The features of the fourth reaction, which are promising for its application in fundamental research, are revealed. Quality of the description of this dynamics by popular computer codes is analyzed.