At the Gammasphere nuclear frontier.Researchers are now starting to take advantage of a new, highly sensitive instrument for detecting gamma rays emitted by atomic nuclei. Located at the Lawrence Berkeley (Calif.) National Laboratory and known as Gammasphere, this nuclear detector consists of a metal sphere more than 2 meters wide, honeycombed with 110 individual sensors. The array enables physicists to study gamma rays from atomic nuclei created in high-energy collisions that fuse different ions together. These fused nuclei typically spin at high rates and often assume unusual shapes, ranging from football to pancake forms (SN: 7/8/95, p. 21). A team led by Cyrus Baktash of the Oak Ridge (Tenn.) National Laboratory has now detected examples of short-lived, rapidly rotating, football-shaped nuclei among the elements strontium strontium (strŏn`shēəm) [from Strontian, a Scottish town], a metallic chemical element; symbol Sr; at. no. 38; at. wt. 87.62; m.p. 769°C;; b.p. 1,384°C;; sp. gr. 2.6 at 20°C;; valence +2. , yttrium yttrium (ĭt`rēəm) [for Ytterby, a town in Sweden], metallic chemical element; symbol Y; at. no. 39; at. wt. 88.9059; m.p. about 1,522°C;; b.p. 3,338°C;; sp. gr. about 4.45; valence +3. Yttrium is a highly crystalline iron-gray metal. , zirconium zirconium (zərkō`nēəm), metallic chemical element; symbol Zr; at. no. 40; at. wt. 91.22; m.p. about 1,852°C;; b.p. 4,377°C;; sp. gr. 6.5 at 20°C;; valence +2, +3, or +4. , and niobium niobium (nīō`bēəm), metallic chemical element; symbol Nb; at. no. 41; at. wt. 92.9064; m.p. about 2,468°C;; b.p. 4,742°C;; sp. gr. 8.57 at 20°C;; valence +2, +3, +4, or +5. . "They are the fastest-spinning nuclei yet observed," Baktash says. The nuclei were synthesized by bombarding Bombarding is the process of 'pumping' a Cold Cathode Lighting tube (otherwise called Neon Signs). Information A detailed process of bombarding can be found here, Bombarding. a nickel-58 target with beams of silicon-28 or sulfur-32 ions. |
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