Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Livermore scientists achieve first full mapping of phonons in plutonium

22.08.2003


Making a landmark event in the history of the experimental investigation of plutonium, scientists from the Lawrence Livermore National Laboratory for the first time have fully mapped the phonons in gallium-stabilized delta plutonium.



The experiment promises to reveal much about the physics and material properties of plutonium and its alloys.

The research, conducted in collaboration with researchers at the European Synchrotron Radiation Facility in Grenoble, France, and the University of Illinois at Champaign- Urbana- and led by Livermore physical chemist Joe Wong will be published in the Aug. 22 edition of Science.


Other Livermore researchers include Daniel Farber, Florent Occelli, Adam Schwartz, Mark Wall and Carl Boro.

Wong’s team took the first measurements of the complete phonon dispersions in a delta plutonium-gallium alloy, using a unique high-resolution inelastic X-ray scattering technique developed at the European Synchrotron Radiation Facility.

Since its discovery in 1941, many technical and safety issues have made experimental observations of plutonium extremely difficult. Measuring the phonon dispersion curves is key to understanding the properties of plutonium materials such as force constants, sound velocities, elasticity, phase stability and thermodynamics.

But for years, scientists have been plagued trying to measure these phonon dispersion curves in plutonium because they were unable to grow the large single crystals necessary for inelastic neutron scattering.

Instead, Wong and his colleagues used an inelastic X-ray scattering technique to impinge a micro-beam from a highly brilliant X-ray synchrotron source on a single grain in a polycrystalline plutonium alloy to make their measurements.

"The phonon dispersions are very fundamental to the understanding of the properties and behavior of plutonium and its alloys," Wong said. "The new phonon data will greatly enhance scientists’ understanding of the transformations and phases plutonium undergoes in different environments and over time. Basic knowledge of this sort is much needed and contributes greatly to the Laboratory’s science-based stockpile stewardship mission to ensure the safety and reliability of the nation’s aging nuclear weapons without testing."


Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by the University of California for the U.S. Department of Energy’s National Nuclear Security Administration.

Anne Stark | EurekAlert!
Further information:
http://www.llnl.gov/
http://www.llnl.gov/PAO

More articles from Physics and Astronomy:

nachricht UNH scientists help provide first-ever views of elusive energy explosion
16.11.2018 | University of New Hampshire

nachricht NASA keeps watch over space explosions
16.11.2018 | NASA/Goddard Space Flight Center

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>