First direct measurement of resonance strengths in 17O({\alpha}, {\gamma})21Ne

TL;DR

This study provides the first direct measurements of resonance strengths in the 17O(α,γ)21Ne reaction, refining reaction rates crucial for astrophysical models of stellar nucleosynthesis.

Contribution

It reports the first in-beam gamma spectroscopy measurements of resonance strengths in 17O(α,γ)21Ne over a specific energy range, clarifying reaction rates relevant to astrophysics.

Findings

Resonances found at E(α)=1002 keV, 1386 keV, 1619 keV.

Measured resonance strengths and gamma-ray branchings.

Results support the Caughlan and Fowler reaction rate.

Abstract

The reaction 17O({\alpha},{\gamma})21Ne has been measured by in-beam gamma spectroscopy for the first time in the energy range E{\alpha} = 750 keV to 1650 keV using highly enriched anodized Ta2(17O)5 targets. Resonances were found at E({\alpha}) = 1002 keV, 1386 keV and 1619 keV. Their strengths and primary gamma-ray branchings are given. The new results exclude the low reaction rate of Descouvemont and support the rate of Caughlan and Fowler. Implications for the neutron poisoning efficiency of 16O in the weak s process are discussed.