Glenn Seaborg: Dedication of the Chemistry Building

Part 3/9

If I could, I would like to spend a little time talking about some of the many fine things that have been going on here at Brookhaven in the Chemistry Department. I can touch on only a few of these achievements; after all, just the list of titles of publications from this department since 1947 is some 85 pages long, and includes nearly 1100 titles. And this does not include any of the excellent chemical research also done at Brookhaven in other departments, such as basic chemical research done in Nuclear Engineering, in Biology and Medicine, or in Physics.

The nuclear chemists, here have effectively exploited the availability of high-energy accelerators - the Cosmotron and the AGS - for detailed studies of the behavior of atomic nuclei under bombardment with fast-moving nuclear particles. Much has been learned about the systematics of these high-energy nuclear reactions, of how the pattern of products formed depends on the choice of target material and the type and energy of projectile. One principal aim of these studies has been to characterize the detailed mechanisms or pathways of the reactions. Another goal is to reach an understanding of the connection between the nuclear reactions observed in complex nuclei and the interactions of elementary particles so intensively studied by the high-energy physicists. Detailed theoretical models and highly advanced computational techniques for the interpretation of high-energy reaction experiments were worked out here in cooperation with scientists at Los Alamos Scientific Laboratory, at the University of Chicago, and at Columbia University. The results of these studies have clarified our knowledge and understanding of the reactions of high-energy particles with complex nuclei. However, they have also showed significant areas in which further improvement and refinement in theory is necessary. This work is currently being pursued. Brookhaven's advanced new computer facilities and staff give strong support to these researches.

This work is closely related to nuclear physics. The skills of the nuclear chemist have been essential for carrying out the chemical separations of the new atoms produced by the bombardment; these separations not only isolate the atoms of interest but also form a vital part of the chain of inference which identifies them. The chemical techniques go hand-in-hand with the study of the characteristic radiations of the radioactive product atoms, which in turn characterize the energy levels of the nuclei which emit them. The detailed study of the radiations and energy levels is called nuclear spectroscopy, a field which is effectively pursued at Brookhaven by both chemists and physicists, often working together in the same research effort. The results give a great deal of significant information about the structure and energetics of nuclei.

Recent work here on emission of protons during radioactive decay has been of great interest, as well as the work with helium-8, which has the largest ratio of neutrons to protons of any known isotope. Careful measurements of the differences of mass between a radioactive nucleus and its daughter product, such as of the pairs hydrogen-3/helium-3 and carbon-14/nitrogen-14 are also significant. These differences give us an upper limit for the rest mass of the neutrino, and so have served as a check on current nuclear theory.

Last Modified: June 28, 2012