First direct measurement of the $^{13}$N($\alpha$,$p$)$^{16}$O reaction relevant for core-collapse supernovae nucleosynthesis

TL;DR

This paper reports the first direct measurement of the $^{13}$N($ ext{alpha}$,$p$)$^{16}$O reaction, crucial for modeling core-collapse supernovae, significantly reducing uncertainties in reaction rates at relevant temperatures.

Contribution

It provides the first direct experimental data for the $^{13}$N($ ext{alpha}$,$p$)$^{16}$O reaction using radioactive ion beams and active-target detection, improving supernova nucleosynthesis models.

Findings

Reaction cross sections measured in the 3.26-6.02 MeV energy range.

Comparison with Hauser-Feshbach calculations shows agreement.

Uncertainties in the reaction rate are significantly reduced.

Abstract

Understanding the explosion mechanism of a core-collapse supernova (CCSN) is important to accurately model CCSN scenarios for different progenitor stars using model-observation comparisons. The uncertainties of various nuclear reaction rates relevant for CCSN scenarios strongly affect the accuracy of these stellar models. Out of these reactions, the $^{13}$N($\alpha$,$p$)$^{16}$O reaction has been found to affect various stages of a CCSN at varying temperatures. This work presents the first direct measurement of the $^{13}$N($\alpha$,$p$)$^{16}$O reaction performed using a 34.6 MeV beam of radioactive $^{13}$N ions and the active-target detector MUSIC (MUlti-Sampling Ionization Chamber) at Argonne National Laboratory. The resulting total $^{13}$N($\alpha$,$p$)$^{16}$O reaction cross sections from this measurement in the center-of-mass energy range of 3.26 - 6.02 MeV are presented and compared with calculations using the Hauser-Feshbach formalism. Uncertainties in the reaction rate have been dramatically reduced at CCSN temperatures.