44Ti, 26Al and 53Mn samples for nuclear astrophysics: the needs, the possibilities and the sources

Exploration of the physics involved in the production of cosmogenic radionuclides requires experiments using the same rare, radioactive nuclei in sufficient quantities. For this work, such exotic radionuclides have been extracted from previously proton-irradiated stainless steel samples using wet chemistry separation techniques. The irradiated construction material has arisen from an extended material research programme at the Paul Scherrer Institute, called STIP (SINQ Target Irradiation Program), where several thousand samples of different materials were irradiated with protons and neutrons of energies up to 570 MeV. In total, 8 × 1017 atoms of 44Ti, ~1016 atoms of 26Al and ~1019 atoms of 53Mn are available from selected samples. These materials may now be used to produce targets or radioactive beams for nuclear reaction studies with protons, neutrons and α-particles. The work is part of the ERAWAST initiative (Exotic Radionuclides from Accelerator Waste for Science and Technology), aimed at facilitating new collaborations between the isotope producers and users from different scientific fields including nuclear astrophysics.