$^{24}$Mg($p$, $\alpha$)$^{21}$Na reaction study for spectroscopy of $^{21}$Na

TL;DR

This study measured the $^{24}$Mg($p$, $ extalpha$)$^{21}$Na reaction to determine energy level properties of $^{21}$Na, aiding astrophysical reaction rate calculations, and identified a new energy level at 6661 keV.

Contribution

It provides new experimental data on $^{21}$Na energy levels, including a previously unobserved level, and applies DWBA analysis to determine angular momentum transfers.

Findings

Discovery of a new level at 6661 keV in $^{21}$Na.

Measured angular distributions for four energy levels.

Comparison with DWBA calculations to determine angular momentum transfer.

Abstract

The $^{24}$Mg($p$, $\alpha$)$^{21}$Na reaction was measured at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory in order to better constrain spins and parities of energy levels in $^{21}$Na for the astrophysically important $^{17}$F($\alpha, p$)$^{20}$Ne reaction rate calculation. 31 MeV proton beams from the 25-MV tandem accelerator and enriched $^{24}$Mg solid targets were used. Recoiling $^{4}$He particles from the $^{24}$Mg($p$, $\alpha$)$^{21}$Na reaction were detected by a highly segmented silicon detector array which measured the yields of $^{4}$He particles over a range of angles simultaneously. A new level at 6661 $\pm$ 5 keV was observed in the present work. The extracted angular distributions for the first four levels of $^{21}$Na and Distorted Wave Born Approximation (DWBA) calculations were compared to verify and extract angular momentum transfer.