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 Dr. Ann Woodin named APS Fellow |
The American Physical Society last month elected to fellowship Livermore researcher Ann Woodin of the Physics and Advanced Technologies Directorate. She was honored for "pioneering the understanding and development of theoretical methods for studying excitation, ionization and dissociation of polyatomic molecules."
She learned about the award from Lab scientist Tom Rescigno, who nominated her.
"My first reaction upon hearing the news was `I'm so excited' to quote the song. It is a great honor to have your peers recognize your contributions to the field in such a manner," she said.
Woodin divides her time between the Lab and UC Davis, where she is a professor in the Department of Applied Sciences and the graduate advisor. Her research is currently focused on what happens to low energy electrons when they interact with molecules.
 Dr. Bill Nellis named as Teller Award recipient |
Bill Nellis, who discovered a method for achieving metallized fluid hydrogen, was recognized for his "contributions of long-standing scientific excellence and impact in and on the field of shock physics." Most noteworthy, according to his award, are his "innovative research efforts in the use of impact-generated shocks to measure the properties of dense, warm molecular and atomic fluids."
Of the award, Nellis said, "I am very proud to receive a fellowship dedicated to Edward Teller. Dr. Teller represents the fusion of good science with a strong influence on national defense."
Nellis, who joined the Lab's B Division in 1973, holds a Ph.D. from Iowa State University and is a fellow of the American Physical Society. He has published 166 papers and holds five patents. All of his work at the Laboratory has involved shock compression of solids, liquids and aerogels.
One of the things the award will enable him to do is work as a visiting fellow at Trinity College of Oxford University. He also plans to start a book on fluids at high pressures and temperatures.
"We can achieve states that no one else in the world can," he said. "We did it using a reverberating shock wave generated with a two-stage light-gas gun, a technology which was developed for weapons-related research."
For more information on the gas gun, please visit the Gas Gun page.
 Dr. Neil Holmes named APS Fellow |
Dr. Neil Holmes of H Division was elected a Fellow of the American Physical Society in November, 1998. Each year, no more than one-half of 1 percent of the society's current membership is recognized by their peers for election to the status of Fellow. The 100-year-old society currently numbers 40,000 physicists worldwide.
APS Fellowship recognizes those who have made advances in knowledge through original research or have made significant and innovative contributions in the application of physics to science and technology.
Holmes' research has emphasized the use of optical and spectroscopic methods for studies of fluids, highly porous materials, and metals. His work has led to a better understanding of weapons physics and the nature of the Earth and the planets Jupiter, Saturn, and Uranus. He was honored with DOE's Excellence for Nuclear Weapons Program award in 1995 and Physics Distinguished Achievement Award for Oustanding Contributions to the Weapons Program in 1990. Holmes will serve as chair of the American Physical Society's Topical Group on Shock Compression of Condensed Matter in 1999.
The citation on his APS certificate reads: "For innovative experimental studies to elucidate and understand the response of condensed matter to dynamic high pressure."
A 21-year veteran of the Laboratory, Holmes joined H Division in 1978 and worked on laser-driven shock-wave experiments at the Janus, Argus, and Shiva lasers. From 1982 to 1990 he served as technical supervisor of the two-stage light gas gun facility specializing in the equation of state, optical diagnostics, and spectroscopy of compressed matter and plasmas.
Positions he has held at the Lab include leader of Physics Equation of State Program, Associate H Division Leader for experiments, leader of the Dynamic Experiments Group, and is currently the Shock Physics Group Leader.
Dr. Holmes received his Ph.D. and master's from Stanford University and his bachelor's in physics from the California Institute of Technology.
For more information on the Shock Physics Group, please visit the Shock Physics Group page.
Doppler Planet Search with a Novel High Efficiency Interferometer-spectrometer |
David Erskine: Principal Investigator
Jian Ge: Astronomer Post Doc
Charles Alcock: Astronomer Consultant
The purpose of this project is to test a new design for a spectrometer having improved abilities to detect planets through the Doppler effect. Furthermore, this new spectrometer concept is fundamentally a different and new approach to spectroscopy than traditional grating-only or interferometer-only methods. Thus we expect spinoff applications in other areas of spectroscopy and metrology. This is an excellant example of cross-disciplinary research, as insight in white light and wide angle interferometer technology garnered in shock wave research at H-Division's two stage gas gun is being applied to a different area of science. It is expected that similarly, development of this new technique of velocimetry in the astronomical context will feedback insight to new applications in shock wave diagnostics and other defense program technology areas.
The new instrument we are developing could be called a fringing spectrometer, and is formed from the combination of a wide angle interferometer and a low resolution grating spectrometer. Its advantages include increased accuracy due to a simpler instrument response, low cost, compact size and portability, higher efficiency, a wide and extendible bandwidth, and a 200 times greater field of view than current spectrometers used for the Doppler detection of extrasolar planets. These characteristics can lead to faster and more reliable detection of smaller mass planets orbiting at greater distances than the planets currently being discovered. A prototypical instrument has been built in building 132 and is currently being tested on sunlight and other spectral sources in the lab, in preparation for eventual use on starlight. For further information about this project contact Dr. David Erskine at 925-422-9545, or visit the Doppler Planet Search Project page.
Discovery of quartz-like CO2 |
To get more information on the discovery of quartz-like CO2, please contact Dr. Choong-Shik Yoo at 925-422-5848, or visit the High-Pressure Physics Group website.
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Robert B. Laughlin, Horst L. Stoermer, and Daniel C. Tsui are the co-winners of the 1998 Nobel Prize in Physics. Stoermer is at Columbia University, Tsui at Princeton, and Laughlin is a professor at Stanford who has strong historical ties to the Physics Directorate at LLNL. Bob arrived in H-Division from Bell Labs in October of 1981. When Bob accepted a position at Stanford in January of 1985, he remained a half-time employee of LLNL and he is still working part time with PAT.
The work for which the prize was awarded is for the discovery of a new form of "quantum fluid" that represents "yet another breakthrough in our understanding of quantum physics and to the development of new theoretical concepts of significance in many branches of modern physics." Bob published the seminal theoretical work for this prize in a pair of papers (Phys. Rev. Lett. 50, 1395 (1983) and Phys. Rev. B 27, 3383 (1983)) in which he explained a phenomenon discovered by Stoermer and Tsui the year before. At the center of Bob's explanation is "a new state of matter, a quantum fluid the elementary excitations of which...are fractionally charged". It is a state in which the electrons, each carrying an indivisible unit of electric charge, can act together in such a way as to appear like a single particle with a fractional charge.
The importance of Bob's work was recognized almost immediately. He received the E. O. Lawrence Award in 1984 from DOE and the Oliver E. Buckley Prize from the American Physical Society in 1986 and now he has received the most prestigious prize in all science.
 The Layered Tektites of South East Asia: A Field Expedition Supported by the National Geographic Society |
Tektites (Etymology: Greek tektos, "molten") are pieces of glass formed when a large meteorite strikes the Earth. Tektites and associated impact melted rock are found in only a few regions on Earth (called tektite strewn fields) and are, in most cases, associated with young impact craters on or near land. Tektite glass looks similar to obsidian glass but can be differentiated by color and chemical composition.
Tektites come in two forms. The more common form, "splash-form tektites" have rounded, aerodynamic shapes such as spheres, tear-drops, dumbbells, and disks when they are well-preserved. The second variety, "layered" or "Muong-Nong-type" tektites, are found in abundance only in southeast Asia. They have blocky, fragmental shapes and commonly display compositional layering and variations in bubble content. Some larger pieces have a surface tektite reminiscent of lava or "breadcrust" lava bombs.
Tektites are similar to shale in composition and have SiO2 contents that range from 68-82%. They have very low water content 0.005% on average. Relative to splash-form tektites, layered tektites are more compositionally heterogeneous, contain more water, and were heated to lower temperatures. These differences, and the fact that layered tektites are found over a more restricted area in southeast Asia, suggest to scientists that splash-form tektites are formed closer to "ground zero" of the impact and layered tektites are formed further from "ground zero."
There are far fewer tektite localities on Earth than there are impact craters. This is because tektites, being made entirely of glass, dissolve slowly with time. We estimate that after 40 million years only one millionth of the original deposit may remain. Therefore, tektites are only preserved in abundance only from large young impact events.
Some scientists have proposed that tektites are material from the Moon. The geochemical evidence from the Moon and from tektites themselves clearly shows that this is unlikely. Furthermore, the clear association of tektites with at least three young craters on Earth provides strong evidence that tektites are a product of terrestrial impact.
UCRL-MI-142025
For questions regarding this web page, contact H Division Web Team
Last modified on 12/13/00