Number 14, December 27, 1990 by Phillip F. Schewe and Ben Stein
THE SOLAR NEUTRINO FLUX shows no day/night or semiannual variations, a conclusion based on 1040 days of monitoring neutrinos from Boron-8 decays in the sun. This finding, recorded at the Kamiokande-II detector in Japan puts limits on the amount by which neutrinos can oscillate from one type to another, a phenomenon suggested to explain the apparent deficit of solar neutrinos measured on Earth. (Upcoming article in Physical Review Letters. Contact Alfred Mann, University of Pennsylvania, 215-898-8155.)
ORGANIC TRANSISTORS are catching up to their amorphous-silicon counterparts with respect to charge carrier mobility, suggesting the possibility that thin-film organic circuits could be used in flat-screen, large-area display electronics, where cheap processing is essential. A group of scientists at the National Centre for Scientific Research in Paris have developed an all-organic transistor with a carrier-mobility of 0.43 cm2/V-s, "comparable to devices made for amorphous silicon." (New Scientist, December 15, 1990.)
THE SOCCER-BALL STRUCTURE OF CARBON -60 and carbon-70, surmised from work done earlier this year, has been further elucidated in NMR, infrared, ultraviolet, x-ray, and electron-diffraction studies. Called Buckminsterfullerene (or Buckyballs), the carbon-60 molecules may, some believe, make possible a new branch of organic chemistry, and enthusiasm for the subject prompted a special session at the recent meeting of the Materials Research Society. Now that macroscopic amounts of the substance are available, scanning tunneling microscope pictures of the solid (fullerite) have been prepared by a group at IBM Almaden (D. Bethune, 408-927-2480) and by a Missouri-MaxPlanck-Arizona (Donald Huffman, Arizona, 602-621-3804) collaboration. (Nature, December 13, 1990.)
THE ASTRO OBSERVATORY , riding on board the Space Shuttle Columbia, found new evidence for the existence of black holes. Measurements included intense x rays, characteristic of matter accreting onto a supermassive object, from the galaxy Markarian 335, and the ultraviolet spectra of various other galaxies and quasars. A number of problems shortened the Shuttle mission, and astronomers were distressed that NASA has not yet scheduled another flight for Astro. (Science News, Dec. 15, 1990.)
TOP AND BOTTOM QUARKS are the chief quarry for proposed accelerator projects in the next five years. Cornell and Stanford are competing for the chance to build "B factories," in which the properties of bottom quarks and the nature of CP violation could be studied. Also Fermilab would like to build a new proton injector ring for the Tevatron Collider, which would provide a more intense beam and a better chance of observing the elusive top quark. These two projects, which would cost between $100 and $160 million, were assigned the highest priority by a Department of Energy panel asked to examine particle-physics goals for the period prior to the SSC. (Physics Today, December 1990.)
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