Study of the 28Si(d,α)26Al Nuclear Reaction at Low Energies

Abstract

26Al is known as a γ-ray emitter in the universe. Since its half-life is only 0.72 My it's the obvious evidence of ongoing nucleosynthesis. This isotope is also known as an origin of an abundance-anomaly of 26Mg observed in meteorites. There is also 26Al production on Earth due to the continuous cosmic ray bombardment. Therefore, a precise knowledge of the production rates for 26Al are needed. In this paper, we present a progress report on our measurements of the 28Si(d,α)26Al nuclear reaction. The experimental protocol consists of three steps: i) target preparation, ii) deuteron irradiations and iii) 26Al off line counting using Accelerator Mass Spectrometry (AMS). Due to accelerator failure, deuteron irradiations had to be interrupted and the number or 26Al produced was insufficient to extract cross sections as expected. In step (ii), given our special geometry requirements we ended up facing the old problem of a goat tethered inside a circular field, which we turned into a tool to fine-tune the beam-target alignment in the micron range.