A radiation detector the size of a wristwatch with a new kind of crystal and a camera that images and identifies radiation sources, operating at a fraction of its former size, is a finalist in Discover magazine's 1997 Awards for Technological Innovation.

The detector, developed at Sandia National Laboratories for applications ranging from detection of smuggled nuclear material to better medical imaging for more precise cancer treatment, is one of 35 finalists to compete for eight technological innovation awards. A second finalist, the Solar Two plant now operated by a consortium led by Southern California Edison, also represents important technical contributions by Sandia. Finalists were announced by Discover Editor-in-Chief Paul Hoffman at the Smithsonian Institution.

The 35 finalists were selected from 4,000 applicants worldwide. Winners will be announced May 31 at Disney's Epcot Center, where the detector technology will also be exhibited from May 30 through June 10. The awards, now in their eighth year, will be featured in the July issue of the 1.2 million-circulation monthly magazine.

Developed by a group led by Ralph James, the compact detectors sense gamma ray emissions. This radiation can serve as a signature for stored nuclear materials and waste, valuable mineral deposits, or cancerous tumors labeled with a radioactive marker. Until recently, spotting the rays required bulky and expensive cryogenic devices. One solution is to find a way to grow large, flawless crystals of cadmium zinc telluride (CZT). These novel semiconductors emit a tiny electronic signal when hit by gamma rays. CZT detectors are already standing guard over dismantled atomic weapons, and cancer- detection applications could be next.

"We are proud to have this recognition for a research and development effort that exemplifies our mission to enhance national security," says Sandia/California VP Tom Hunter. "Ralph's work is an example of the way Sandia creates technological solutions for pressing problems such as providing protection for nuclear materials," he says. "These innovations also have the potential to address important needs in our society, such as enhanced environmental monitoring and improved medical evaluation and treatment."

Sandians are also represented by a finalist in the "environment" category. The sun provides plenty of energy - but it isn't easy to harness. The Solar Two power plant does it with 2,000 giant, computer-aimed mirrors that follow the sun and reflect its rays onto pipes full of molten salt. The hot salt, which can retain most of its heat for 12 hours after sundown, then produces steam to drive turbines, generating electricity for 10,000 homes. The pilot plant is a warm-up for a much larger commercial plant down the road.

Sandia "has led the effort in the development of molten-salt technology," says Mike Prairie. "Solar Two's use of the molten-salt system will show that this technology is capable of being commercialized."

Sandia is a multiprogram Department of Energy laboratory operated by a subsidiary of Lockheed Martin Corp. With main facilities in Albuquerque, N.M., and Livermore, Calif., Sandia has broad-based research and development programs contributing to national security, energy and environmental technologies, and economic competitiveness.