Measuring low-energy ([formula omitted]) reaction cross sections using an extended gas target and gas recirculator

Abstract

Direct measurements of (α,p) reactions of astrophysical interest with radioactive beams presents serious challenges because of the difficult nature of helium targets and the typical low intensities of the beams. To address this, a new technique has been developed for measurements of low-energy (α,p) reactions with heavy ion beams using an extended 4He gas target and a newly developed gas recirculating system. The system was used to measure the 4He(19F, 1H)22Ne reaction as a demonstration. Excitation functions of the 19F(α,p)22Ne and 19F(α,p′)22Ne∗ reactions were successfully measured to show the viability of this technique. Details of the approach and future plans are given.