Gamma rays from the decay of certain radionuclides, e.g. the prominent 26Al (t1/2 = 0.72 Ma) and 44Ti (t1/2 = 60 a), can be traced in our galaxy and verify in this way ongoing nucleosynthesis. The relevant stellar scenarios and their production mechanisms are an essential key for understanding the cosmic evolution of the elements. In general, well-established data on production rates of long-lived radionuclides, important for the various nucleosynthesis processes, are highly desired. The potential of AMS as a powerful tool for probing nucleosynthesis will be demonstrated by means of some prime examples. A survey of recent applications of AMS to nuclear astrophysics is given and an overview on the recent measurement program at the Vienna Environmental Research Accelerator (VERA) as well as at other laboratories for quantifying such long-lived radionuclides will be presented. The strength of AMS is definitely its unrivaled sensitivity in quantifying minute concentrations of long-lived radionuclides. Standard techniques require a preceding irradiation of suitable sample material and the product is subsequently measured offline using AMS. However, the potential and limits of AMS will also be discussed detecting online-produced nuclides using inverse-kinematics reactions followed by a low-background high-energy analyzing system. At VERA a measurement program is underway for studying neutron and proton capture reactions for various isotopes. Because of very small cross-sections both, a high overall efficiency of the measurement and also a very low background interference has to be achieved. Actual detection limits and measurement techniques at VERA for various isotopes will be presented. New technological developments in isobar suppression makes 41Ca and also 36Cl detection accessible to AMS facilities like VERA [1]. E.g. the determination of the cross section for the 40Ca(n,γ)41Ca reaction at astrophysical interesting neutron energies is in progress.
[1] P. Steier, R. Golser, W. Kutschera, A. Priller, K. Vorderwinkler, A. Wallner, C. Vockenhuber, AMS of 41Ca and 36Cl at a 3-MV tandem with a ΔTOF detector, Contribution to this conference.
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