Precision measurements on oxygen formation in stellar helium burning with gamma-ray beams and a Time Projection Chamber.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 34635664.
- Also identified by DOI 10.1038/s41467-021-26179-x and PMC identifier 8505630.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The carbon/oxygen (C/O) ratio at the end of stellar helium burning is the single most important nuclear input to stellar evolution theory. However, it is not known with sufficient accuracy, due to large uncertainties in the cross-section for the fusion of helium with <sup>12</sup>C to form <sup>16</sup>O, denoted as <sup>12</sup>C(α, γ)<sup>16</sup>O. Here we present results based on a method that is significantly different from the experimental efforts of the past four decades. With data measured inside one detector and with vanishingly small background, angular distributions of the <sup>12</sup>C(α, γ)<sup>16</sup>O reaction were obtained by measuring the inverse <sup>16</sup>O(γ, α)<sup>12</sup>C reaction with gamma-beams and a Time Projection Chamber (TPC) detector. We agree with current world data for the total reaction cross-section and further evidence the strength of our method with accurate angular distributions measured over the 1<sup>-</sup> resonance at E<sub>cm</sub> ~ 2.4 MeV. Our technique promises to yield results that will surpass the quality of the currently available data.