A proposed direct measurement of cross section at Gamow window for key reaction $^{19}$F($p$,$\alpha$)$^{16}$O in Asymptotic Giant Branch stars with a planned accelerator in CJPL

TL;DR

This paper discusses a planned direct measurement of the $^{19}$F($p$,$eta$)$^{16}$O reaction cross section at Gamow energies using the Jinping Underground Nuclear Astrophysics laboratory to better understand fluorine abundances in AGB stars.

Contribution

It introduces a new experimental approach to measure the key stellar reaction at Gamow window energies with the upcoming accelerator at CJPL.

Findings

Design of the experimental setup and background estimation.

Feasibility of measuring the reaction underground.

Expected impact on stellar nucleosynthesis models.

Abstract

In 2014, the National Natural Science Foundation of China (NSFC) approved the Jinping Underground Nuclear Astrophysics laboratory (JUNA) project, which aims at direct cross-section measurements of four key stellar nuclear reactions right down to the Gamow windows. In order to solve the observed fluorine overabundances in Asymptotic Giant Branch (AGB) stars, measuring the key $^{19}$F($p$,$\alpha$)$^{16}$O reaction at effective burning energies (i.e., at Gamow window) is established as one of the scientific research sub-projects. The present paper describes this sub-project in details, including motivation, status, experimental setup, yield and background estimation, aboveground test, as well as other relevant reactions.