Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers move closer to switching nuclear isomer decay on and off

10.04.2007
Livermore researchers have moved one step closer to being able to turn on and off the decay of a nuclear isomer.

The protons and neutrons in a nucleus can be arranged in many ways. The arrangement with the lowest energy is called the ground state and all others are called excited states. (This is analogous to the ground and excited states of electrons in an atom except that nuclear excited states are typically thousands of times higher in energy.) Excited nuclear states eventually decay to the ground state via gamma emission or to another nucleus via particle emission. Most excited states are short-lived (e.g., billionth of a second). However, a few are long-lived (e.g., hours) and are called isomers.

Turning the decay on and off is key to using isiomers as high-energy density storage systems such as batteries.

Researchers at Livermore studied an isomer of Thorium-229. This isomer is unique in that its excitation energy is near optical energies, implying that one day scientists may be able to transition Th229 nuclei between the ground and isomeric states using a table-top laser.

"This would then be the first time human control would be exerted over nuclear levels," said Peter Beiersdorfer, an LLNL physicist and co-author of a paper that appears in the April 6 issue of Physical Review Letters. "This only works if the laser is tuned to exactly the correct energy."

For years, researchers have been fascinated with this isomer because it could lead to new science and technology breakthroughs. Among them are: a quantum many-body study; a clock with unparallel precision for general relativity tests; a superb qubit (a quantum bit) for quantum computing; testing the effects of the chemical environment on nuclear decay rates. Isomers also may serve as a battery for storing large amounts of energy.

However, before these exotic studies can be performed, an accurate determination of the isomer’s excitation energy above the ground state is needed. In the most recent research, Livermore scientists, along with colleagues from Los Alamos National Laboratory and NASA Goddard Space Flight Center, have made the most accurate measurement of this energy difference using an indirect technique.

"Our measurement is more accurate and differs significantly from prior results. This may explain why scientists have failed to directly see this transition. Frankly, they were looking in the wrong place," said Bret Beck, an LLNL physicist and lead-author on the paper.

The next step will be to use a laser or a synchrotron tuned to the exact energy of the spacing between the two levels and observe the transition from the ground state to the isomeric state.

Once laser excitation has proven possible, helping an excited level decay (and thus give off energy) can be tackled. "But for building a more precise clock than we have today, or building a quantum computer, excitation may be all that’s needed," Beiersdofer said.

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

More articles from Physics and Astronomy:

nachricht Enhancing the quantum sensing capabilities of diamond
23.11.2017 | The Hebrew University of Jerusalem

nachricht Quantum optics allows us to abandon expensive lasers in spectroscopy
22.11.2017 | Lomonosov Moscow State University

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: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Underwater acoustic localization of marine mammals and vehicles

23.11.2017 | Information Technology

Enhancing the quantum sensing capabilities of diamond

23.11.2017 | Physics and Astronomy

Meadows beat out shrubs when it comes to storing carbon

23.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>