Accelerator Mass Spectrometry: From Nuclear Physics to Dating

Abstract

One of my former teachers in nuclear physics, H Morinaga, once pointed out to me that essentially all the fundamental discoveries in nuclear physics were done without the use of accelerators. At first, this statement seemed extremely exaggerated, but now I think there is much truth in it. Once we build an instrument to investigate a specific problem we have already realized the existence of the problem and do not need the instrument to discover it. It is almost inevitable that the most interesting discoveries with a new technique will be made in fields for which the technique was not invented. Accelerators, built for nuclear physics, produced a great amount of data on nuclear structure and forces but the most fundamental discoveries were made in elementary particle physics. In any case, for almost 40 years the sole purpose of accelerators was to deliver beams of ever increasing energy and versatility to perform experiments after the accelerator. The analytic properties of accelerators were almost completely ignored even after the very early use of the Lawrence cyclotron at Berkeley as a mass spectrometer to discover 3He in nature (Alvarez and Cornog, 1939 a; b). The enormous analytic power of accelerators is now fully recognized, but the joy of the revival is mixed with some disappointment that the great prospects for studying 14C problems (Muller, 1977; Bennet et al, 1977; Nelson, Korteling, and Stott, 1977) have not yet been fulfilled. Fortunately, some of the papers of this conference show that a big step forward has been taken. But in view of what I said before it is not surprising that most of the studies were actually done with other radioisotopes.