Re-measurement of the ${}^{33}$S($\alpha$,p)${}^{36}$Cl cross section for Early solar system enrichment

Abstract

Short-lived radionuclides (SLRs) with half-lives less than 100 Myr are known to have existed around the time of the formation of the solar system around 4.5 billion years ago. Understanding the production sources for SLRs is important for improving our understanding of processes taking place just after solar system formation as well as their timescales. Early solar system models rely heavily on calculations from nuclear theory due to a lack of experimental data for the nuclear reactions taking place. In 2013, Bowers et al. measured ${}^{36}$Cl production cross sections via the ${}^{33}$S($\alpha$,p) reaction and reported cross sections that were systematically higher than predicted by Hauser-Feshbach codes. Soon after, a paper by Peter Mohr highlighted the challenges the new data would pose to current nuclear theory if verified. The ${}^{33}$S($\alpha$,p)${}^{36}$Cl reaction was re-measured at 5 energies between 0.78 MeV/A and 1.52 MeV/A, in the same range as measured by Bowers et al., and found systematically lower cross sections than originally reported, with the new results in good agreement with the Hauser-Feshbach code TALYS. Loss of Cl carrier in chemical extraction and errors in determination of reaction energy ranges are both possible explanations for artificially inflated cross sections measured in the previous work.

References in corpus (7)

• Short-lived Nuclei in the Early Solar System: Possible AGB Sources
• The production of short-lived radionuclides by new non-rotating and rotating Wolf-Rayet model stars
• Injection of Short-Lived Radionuclides into the Early Solar System from a Faint Supernova with Mixing-Fallback
• The 40Ca(alpha,gamma)44Ti reaction in the energy regime of supernova nucleosynthesis
• Short-lived radioactivity in the early Solar System: the Super-AGB star hypothesis
• Measurement of the 33S(α,p)36Cl cross section: Implications for production of 36Cl in the early Solar System
• Unexpected properties of the ${}^{33}$S($\alpha$,p)${}^{36}$Cl reaction cross section at low energies

Cited by in corpus (5)

• Radioactive nuclei from cosmochronology to habitability
• The activation method for cross section measurements in nuclear astrophysics
• First measurement of ${}^{30}$S+$\alpha$ resonant elastic scattering for the ${}^{30}$S($\alpha$,p) reaction rate
• Measurement of ${}^{34}$S(${}^3$He,p)${}^{36}$Cl cross sections for early solar system nuclide enrichment
• Cross sections of $\alpha$-induced reactions slightly below doubly-magic ${}^{40}$Ca from the statistical model