LLNL Home S&TR Home Subscribe to S&TR Send Us Your Comments S&TR Index
Spacer Gif


Spacer Gif











The Laboratory
in the News

Homeland security technology is licensed
In a premier example of homeland security technology moving to the marketplace, the Laboratory signed a licensing agreement with ORTEC Products of Oak Ridge, Tennessee, to commercialize RadScout, a lightweight, portable radiation detector and analyzer.
The signing of the licensing agreement took place on June 18, 2003, in a ceremony at the Laboratory attended by National Nuclear Security Administration’s Administrator Linton Brooks.
Developed within Livermore’s Defense and Nuclear Technologies Directorate, RadScout is intended for emergency first-response teams and inspectors who need rapid detection and identification of material so they can determine the nature and scope of a possible nuclear threat.
RadScout weighs about 9 kilograms. Its miniaturized refrigeration system cools to about 90 kelvins (–280°F) and eliminates heavy, bulky liquid nitrogen cooling for the device’s germanium crystal, which is the heart of the device’s detection capability. RadScout measures neutrons and gamma rays emitted by radioactive materials and then analyzes them to identify their sources.
The high-performance, high-resolution portable system can be used at border crossings, on cargo ship docks, and in transportation terminals to differentiate between potentially dangerous radioactive materials and otherwise harmless radiation sources.
Contact: Raymond Pierce (925) 423-8465 (pierce13@llnl.gov).

Hot on the trail of a solar mystery
Livermore physicist Margarita Ryutova and Theodore Tarbell, a researcher from Stanford–Lockheed Martin Solar and Astrophysics Laboratories in Palo Alto, California, have solved a long-standing astrophysics mystery: Why is the Sun’s corona, or uppermost layer of the solar atmosphere, 300 times hotter than the 6,000-degree solar surface, and how does the energy from the Sun’s relatively cool surface get transferred to the corona to make it so much hotter than the surface?
Ryutova and Tarbell began to solve this mystery by observing a narrow, 300-kilometer transition region at the bottom of the corona. Using instruments on the Solar and Heliospheric Observatory and the Transition Region and Coronal Explorer, they observed that the collision of magnetic fields of small-scale flux tubes in the photosphere causes a series of regular actions. These actions start from the magnet flux reduction, pass through shock formation, and appear in the transition region as microflares, hot supersonic plasma jets, and explosive events.
“For the first time,” says Ryutova, “we could see these shocks in action. When shocks collide, the energy of a system is first squeezed into a very small volume and then gets violently released.”
The events are similar to the shaped charges found in modern high explosives. A shaped charge focuses all of its energy on a single line, making it extremely accurate and powerful. Likewise, colliding shock fronts produce dramatic effects in the form of microflares and plasma jets in the solar transition region.
Ryutova and Tarbell’s findings provide insight not only into the origin of the solar transition region, but also into how every production, transfer, and release may occur throughout the Sun’s and other stars’ atmospheres. Their results may help explain the energy output of other cosmic objects that have magnetic fields and gravitation. Results appear in the May 15, 2003, issue of Physical Review Letters available at prl.aps.org.
Contact: Margarita Ryutova (925) 423-7858 (ryutova1@llnl.gov).

Monitoring Middle East quakes
Last year, two earthquakes with Richter magnitudes of 5.1 and 4.3 shook the United Arab Emirates (UAE). The ground motion resulted in damage to structures and minor injuries and surprised people because earthquakes are rare for this region.
In October 2002, Laboratory seismologists Keith Nakanishi and Arthur Rodgers traveled to the UAE to talk with various universities about a scientific partnership to record seismic ground motion. The geology department of UAE University in Al Ain welcomed the possibility for collaboration.
In May 2003, Rodgers and technician Pat Lewis installed seismic monitoring stations near Al Ain and Al Hail in a cooperative project with UAE University. This equipment records tiny ground motions, including small earthquakes and explosions in the UAE and large, distant earthquakes. The university’s geology department set up a laboratory to analyze data collected through the seismic stations.
“The Persian Gulf,” says Rodgers, “is a good place to collect important seismic data, because little or no data have been recorded there. Data from these stations will be used to learn about earthquakes and earth structure in and around the UAE.” The Zagros Mountains in Iran, which sit just across the Persian Gulf from the UAE, are active seismic centers, while the Semail Ophiolite, a mountain range that spans Oman and the UAE, is relatively aseismic.
“The new seismic stations will be used to learn where small earthquakes occur and help define seismically active faults,” says Rodgers. “This information will help our Emirati colleagues know where to expect and be better prepared for possible future earthquakes.”
Rodgers and his colleagues hope to expand their efforts to other countries, so that eventually a network of seismic stations can monitor earthquake activity throughout the Middle East.
Contact: Arthur Rodgers (925) 423-5018 (rodgers7@llnl.gov).



Back | S&TR Home | LLNL Home | Help | Phone Book | Comments
Site designed and maintained by IBIS Internet Publishing Team

Lawrence Livermore National Laboratory
Operated by the University of California for the U.S. Department of Energy

UCRL-52000-03-9 | September 5, 2003