in the News
Leland W. Younker
This Model Can Take the
The Best and the Brightest
Come to Livermore
A View to a Kill
Biological Research Evolves
in the News
detectors tested, developed
Livermore researchers are
testing commercial instruments and developing new technologies to
detect nuclear materials inside cargo containers. Funded by the
National Nuclear Security Administration, this work aims to prevent
the smuggling of nuclear materials into the U.S. by airplane, ship,
rail, or truck.
In June, Laboratory researchers
tested 19 commercially available handheld instruments that government
agencies are using or might use to detect nuclear materials in cargo
One of our areas of
expertise is understanding what goes into a nuclear weapon, so we
know how to test equipment to find the materials for which different
government agencies are searching, says William Dunlop, leader
of Livermores Proliferation Prevention and Arms Control Program.
Livermore researchers, experienced
in designing and testing nuclear weapons, have assessed possible
improvised nuclear devices as part of the Laboratorys nonproliferation
programs, according to Dunlop. This expertise is bolstered by the
programs capabilities in detecting trace elements.
Livermore and other researchers
are also developing new and enhanced radiation detection systems.
One new device is Cryo3, a mobile, handheld detector. Developed
by researchers at Lawrence Livermore and Lawrence Berkeley national
laboratories, Cryo3 is a high-resolution germanium detector cooled
mechanically by a compact, low-power microcryocooler instead of
by liquid nitrogen. Once the device has been tested and approved
for field use, the Laboratory will help train personnel in using
the new technology.
Contact: William Dunlop (925) 422-9390 (firstname.lastname@example.org).
facility puts the pressure on materials
In July 2002, the High Pressure
Collaborative Access Team (HP-CAT) began work on the newest research
facility at the Advanced Photon Source (APS) at Argonne National
Laboratory in Illinois. This $10-million research facility will
contain beamlines for the intense, high-energy APS. Researchers
will use the facility to study in high resolution the structure
and behavior of materials under high pressures and varying temperatures.
HP-CAT is made up of Livermores
High-Pressure Physics Group from the Physics and Advanced Technologies
Directorate; the High Pressure Science and Engineering Center at
the University of Nevada at Las Vegas; the Carnegie Institution
of Washington Geophysical Laboratory in Washington, D.C.; and Argonne
Funded in part by the Department
of Energys Office of Defense Programs and Office of Science
and scheduled for completion by May 2003, the new research facility
will advance high-pressure science by allowing new types of experiments
to be performed. For example, scientists will be able to measure
the dynamics of electrons, atoms, and nuclei of complex materials
as functions of pressure, temperature, and time. It will also allow
the use of new-generation high-pressure devices such as large-volume
diamond-anvil cells. Its goals are to advance high-pressure synchrotron
radiation research and establish a leading center of high-pressure
research accessible to the scientific community at large.
At Livermore, weve
invested in this beamline because it is an enabling capability for
the Stockpile Stewardship Program, says William Goldstein,
associate director for Physics and Advanced Technologies. The
highly intense, high-energy x-ray beam will allow us to characterize
the structure of high explosives and of the low-symmetry phases
of plutonium with unprecedented precision.
Contact: Choong-Shik Yoo (925) 422-5848 (email@example.com).
Age of oldest
objects in solar system determined
A team of geochemists, including
Livermores Ian Hutcheon, has accurately dated calciumaluminum
inclusions (CAIs), the oldest objects in our solar system, at 4.57
billion years old. The team also determined that chondrules, another
of the earliest objects in the solar system, are 2 to 3 million
years younger than CAIs. By determining the age of CAIs and
chondrules, we can better date asteroids and planets and learn more
about the early history of the solar system, says Hutcheon.
Hutcheon, Yuri Amelin of
the Royal Ontario Museum, Alexander Krot of the University of Hawaii,
and Alexander Ulyanov of Moscow State University published their
findings in the September 6, 2002, issue of Science.
Using mass spectrometers
to study CAIs and chondrules, the team determined the age of the
objects by measuring the decay rate of uranium-238, which is found
in both objects, as it decays into lead. With an ion microprobe,
Hutcheon then dated CAIs and chondrules by detecting the decay of
aluminum-26, also found in both objects, into magnesium-26.
Aluminum-26 decays much faster
than uranium-238. By comparing the lead and magnesium isotope content
in the CAIs and chondrules, the team determined with great precision
both how old the objects are and the difference in age between CAIs
CAIs and chondrules are millimeter-size
objects found in primitive meteorites. They formed when dusty regions
of the solar nebula were heated to high temperatures. The dust melted
and then crystallized, forming first CAIs and then chondrules.
Larger objects, such as asteroids
and planets, took longer to form and are about 10 to 50 million
years younger than CAIs and chondrules.
Contact: Ian Hutcheon (925) 422-4481 (firstname.lastname@example.org).
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November 15, 2002