New Detector

Weapons Lab Rolls Out New Radiation Detectors

L I V E R M O R E, Calif., April 18 — A cell phone that will be able to tell the difference between a "dirty bomb" and someone who's undergone radiation treatment is among the next generation of anti-terrorism tools being worked on by national weapons lab scientists.

The device, known as RadNet, is designed to make calls, surf the Web, act as a Personal Digital Assistant, pinpoint locations with Global Positioning System technology and sniff out nuclear materials with a cutting-edge sensor. It is one of several national security projects under development at Lawrence Livermore National Laboratory.

"It almost sounds like science fiction, but it's here today," said Simon Labov, director of the new Radiation Detection Center at Lawrence Livermore, which celebrated its formal opening Thursday with a display of the RadNet and other devices.

U.S. Rep. Ellen Tauscher, D-Calif., who was at the lab for the opening and for a daylong conference of emergency response officials, called the projects "the kind of work and the kind of science that is fundamental to our being able to protect the American people from weapons of mass destruction."

Lab officials showed off their work with theatrical flair, whipping away white cloths from some prototypes.

"This is called UltraSpec," Labov said as he displayed the Ultra-High Resolution Gamma Ray and Neutron Spectrometers. "No other instrument like it in the world."

The Ultra-Spec uses extremely low temperatures — within one degree of absolute zero, or -459 degrees Fahrenheit — to measure gamma rays from nuclear materials that might be present in terrorist bombs and weapons. It works by recording, very precisely, the rise in temperature when a single gamma ray hits the detector's superconducting material, which is usually tin.

"At these low temperatures we get incredible sensitivity," Labov said.

Much of the technology on display Thursday uses gamma ray detection because gamma rays travel farther than other substances emitted by nuclear material and are easier to spot and identify, Labov said. Nuclear material also emits neutrons, which is part of some of the detection technology.

RadNet grabbed a lot of the attention Thursday with its small size — in the range of a cellular phone circa 1995 — and big agenda.

Scientists hope to have prototypes ready for testing within a few months and could have the devices ready for action in about two years.

— The Associated Press