Peña gives go-ahead for subcritical tests

Secretary of Energy Federico Peña in March gave the go-ahead for conducting subcritical experiments. Conducted nearly 1,000 feet underground, the experiments will test the basic properties of small quantities of plutonium driven to high pressures using conventional explosives. No nuclear energy will be generated by the experiments. Data on the properties of plutonium will improve the accuracy of the computer simulations that ultimately will provide a level of confidence in weapons reliability and safety, previously assured by nuclear testing.
"Subcritical experiments are essential to our commitments to a world free of nuclear testing, a reliable nuclear deterrent, and are fully consistent with the Comprehensive Test Ban Treaty (CTBT)," Peña said in a statement.
"In addition, these experiments complement other elements of DOE's Stockpile Stewardship and Management Program, such as the National Ignition Facility and the Accelerated Strategic Computing Initiative, additional tools that will help supply the confidence in stockpile safety and reliability the President has required in order to support the CTBT," he said.
The first in a series of subcritical experiments is scheduled by Los Alamos for June. The second, by LLNL, will follow sometime later.
Contact: LLNL Media Relations (510) 422-4599 (

Scientists simulate earthquake ground-motion patterns

Scientists at Lawrence Livermore and the University of California at Berkeley have announced results of a study that models the localized severity of ground motion during a major earthquake along the Hayward fault. The fault runs beneath a densely populated section of the eastern San Francisco Bay Area.
Using one of the world's most powerful supercomputers at Lawrence Livermore, Laboratory computer scientist Shawn Larsen teamed with Berkeley seismologists Mike Antolik and Doug Dreger to simulate expected ground motions for a magnitude 7.1 earthquake along the Hayward fault beginning south of Fremont and rupturing 50 miles northwest to San Pablo Bay.
The researchers developed a computer movie based on this scenario that shows seismic waves propagating throughout the Bay Area and impacting different regions with varying degrees of severity.
"Ultimately it's our goal that those responsible for earthquake retrofit and new structure design can take our findings and combine them with current approaches to make better engineering decisions," said Larsen.
The researchers announced their findings at the Seismological Society of America annual meeting, held in April in Honolulu. Their simulations use a sophisticated computer code developed at Livermore and a seismic velocity model developed at Berkeley.
Contact: Shawn Larsen (510) 423-9617 (

Defense research yields commercial benefits

Defense research at Lawrence Livermore may help U.S. companies get a head start in the fiercely competitive international computer chip market, according to Dena Belzer, author of a new study about the Laboratory's effect on the economy.
Belzer, a principal consultant with Bay Area Economics in Berkeley, quoted industry giants Intel Corp. and Microsoft as saying that breakthroughs at Lawrence Livermore have been critical to putting more information onto tiny microchips. The companies said the Lab's cutting-edge research tools and wide pool of scientists from diverse disciplines enabled microchip breakthroughs such as EUV lithography, a technique for putting information on chips more precisely with strokes that are about a thousandth of the width of a human hair.
Belzer's report said that the planned National Ignition Facility laser could push the state of the art in several technology areas over the next 10 to 15 years but cautioned that "economic benefits can only be realized if the national labs continue to have strong interactive relationships with private industry."
Contact: LLNL Media Relations (510) 422-4599 (

Lawrence Livermore's high profile in arms control

In an address to Lawrence Livermore employees in April, Ambassador Thomas Graham, Jr., U.S. negotiator and special representative of the President at the U.S. Arms Control and Disarmament Agency, applauded the Laboratory's contributions and its high-profile role in achieving a global treaty to end nuclear testing.
According to Graham, Lawrence Livermore was the only one of the nation's three nuclear weapons laboratories represented directly on the U.S. negotiating team for the test ban.
The Laboratory's representative, physicist William Dunlop, "was one of the top 10 people on our negotiating delegation," Graham said. "He and the Lab . . . made a very important contribution to developing negotiating positions and ultimately to the negotiations of the [Comprehensive Test Ban Treaty].
"More and more people in recent years have looked to the [national] labs for support in arms control and nonproliferation because they have a lot to offer. And a lot of it is world-class and unique," he said. He went on to name specialized sensors and other technology for monitoring treaty compliance as examples.
Contact: LLNL Media Relations (510) 422-4599 (
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