Radiative Alpha Capture on ⁷Be with DRAGON at Energies Relevant to the $\varvec{\nu }$p-Process

Abstract

The origin of the p-nuclei, has been a long-standing puzzle in nuclear astrophysics. The $\nu$p-process is a candidate for the production of the light p-nuclei, but it presents high sensitivity to both supernova dynamics and nuclear physics. It has been recently shown that the breakout from pp-chains through the ⁷Be$(\alpha ,\gamma )$¹¹C reaction, which occurs prior to $\nu$p-process, can significantly influence the reaction flow, and subsequently the production of p-nuclei in the $90<{\text {A}}<110$ region. Nevertheless, this reaction has not been studied well yet in the relevant temperature range - T = 1.5–3 GK. To that end, the first direct study of important resonances of the ⁷Be$(\alpha ,\gamma )$¹¹C reaction with unknown strengths using DRAGON was recently performed at TRIUMF. The reaction was studied in inverse kinematics using a radioactive ⁷Be (t$_{1/2}$ = 53.24 d) beam provided by ISAC-I and two resonances above the ¹¹C $\alpha$-separation energy - Q$_{\alpha } = 7543.62$ keV - were measured. The experimental details, in particular how the recoil transmission and BGO efficiencies were accounted for considering the large cone angle for this reaction, will be presented and discussed alongside some preliminary results.