Detection of the Low Energy Recoil 3He in the Reaction 2H(8He,3He)7H

Abstract

Investigation of the 7H-system in the experiment conducted at the fragment separator ACCULINNA-2 in the 8He(2H,3He)7H reaction requires to detect the recoil 3He ions with energy down to 6 MeV. For this purpose two $$\Delta E{\text{—}}E$$ particle telescopes are used, with each telescope having in front a thin (20-μm) Si strip detector ($$\Delta E{\text{—}}SSD$$). The maps of thickness heterogeneity of the thin detectors were determined by measuring the energy losses of the 226Ra α-particles. The adopted thickness normalization method provides a good identification of the 3He nuclei being recorded in the presence of a high 4He background. Two approaches were used for calculating the energy losses of the identified 3He and 4He reaction ejectiles and reconstructing their energy values available at the exit from the deuterium target. The developed techniques were applied for the 7H missing-mass reconstruction.