Physics of rapidly rotating nuclei

JUN 01, 1979

The study of nuclei with high angular momenta illuminates nuclear shell structure, the collective, often superfluid, motion of nucleons, and elastic deformation of nuclei.

DOI: 10.1063/1.2995584

Aage Bohr

Ben R. Mottelson

In recent years, a new field of nuclear research has been opened through the possibility of studying nuclei with very large values of the angular momentum. This development has been closely associated with the study of heavy‐ion reactions, since collisions between two heavy nuclei are especially effective in producing metastable compound systems with large angular momenta. The study of such rapidly rotating nuclear systems provides the opportunity for exploring new aspects of nuclear dynamics. In figure 1 we show a multiple‐coincidence spectrometer for studying gamma‐ray cascades from the decay of these high‐angular‐momentum states. It comprises eighteen NaI detectors arranged around an on‐line target; seven of the detectors and their photo‐multipliers are visible in the photo. The arrangement gives high sensitivity to gamma‐ray cascades, which in some cases exceed thirty consecutive gamma rays. The spectrometer was constructed at the Niels Bohr Institute and is being used in a Copenhagen‐Darmstadt collaboration.

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More about the Authors

Aage Bohr. Niels Bohr Institute.

Ben R. Mottelson. Niels Bohr Institute.