Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Z produces fusion neutrons, Sandia scientists confirm

07.04.2003


Huge pulsed power machine enters fusion arena



Throwing its hat into the ring of machines that offer the possibility of achieving controlled nuclear fusion, Sandia National Laboratories’ Z machine has created a hot dense plasma that produces thermonuclear neutrons, Sandia researchers announced today at a news conference at the April meeting of the American Physical Society in Philadelphia.

The neutrons emanate from fusion reactions within a BB-sized deuterium capsule placed within the target of the huge machine. Compressing hot dense plasmas that produce neutrons is an important step toward realizing ignition, the level at which the fusion reaction becomes self-sustaining.


The amount of energy a larger successor to Z could bring to bear offers the still-later possibility of high-yield fusion -- the state in which much more energy is released than is needed to provoke the reaction initially to occur. The excess energy could be used for applications such as the generation of electricity, said Tom Mehlhorn, a project leader on the machine.

Z causes reactions to occur neither by confining low density plasmas in dimensionally huge magnetic fields, as do tokomaks, nor by focusing intense laser beams on or around a target, as in laser fusion, but simply through the application of huge pulses of electricity applied with very sophisticated timing. The pulse creates an intense magnetic field that crushes tungsten wires into a foam cylinder to produce X-rays. The X-ray energy, striking the surface of the target capsule embedded in the cylinder, produces a shock wave that compresses the deuterium within the capsule, fusing enough deuterium to produce neutrons.

"Pulsed power electrical systems have always been energy-rich but power-poor," said Ray Leeper, a Sandia manager. "That is, we can deliver a lot of energy, but it wasn’t clear we could concentrate it on a small enough area to create fusion. Now it seems clear we can do that."

A partial confirmation of the result came about when theoretical predictions and lab outcomes were determined to be of the same order of magnitude. Predictions and measurements of the neutron yield were both of the order of 10 billion neutrons. The predicted neutron yield depends on the ion density temperature and volume. Those quantities were independently confirmed by X-ray spectroscopy measurements.

Neutron pulses were observed as early as last summer but researchers were wary that the output was produced by interactions between the target and ions generated by Z’s processes, rather than within the capsule itself. Ion-generated neutrons were not the point of the experiment, since they would not scale up into a high-yield event in any later, more powerful version of Z.

But a series of experiments completed in late March demonstrated that the production was within the capsule itself. To show this, researchers inserted xenon gas within the capsule. The gas prevented the capsule from getting hot during compression. Thus, the neutron yield dropped dramatically, as predicted.

The action takes place within a container the size of a pencil eraser, called a hohlraum, at the center of the Z machine, itself a circular device about 120 feet in diameter.

Sandia researchers Jim Bailey and Gordon Chandler led the experimental team and Steve Slutz performed theortical calculations. Sandian Carlos Ruiz and Gary Cooper of the University of New Mexico performed the neutron measurements.


Sandia Media Relations Contact: Neal Singer, (505) 845-7078, nsinger@sandia.gov

Neal Singer | EurekAlert!
Further information:
http://www.sandia.gov/news-center/news-releases/2003/nuclear-power/Zneutrons.html
http://www.sandia.gov

More articles from Power and Electrical Engineering:

nachricht Smart windows that self-illuminate on rainy days
29.05.2020 | Pohang University of Science & Technology (POSTECH)

nachricht Skoltech scientists get a sneak peek of a key process in battery 'life'
28.05.2020 | Skolkovo Institute of Science and Technology (Skoltech)

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Biotechnology: Triggered by light, a novel way to switch on an enzyme

In living cells, enzymes drive biochemical metabolic processes enabling reactions to take place efficiently. It is this very ability which allows them to be used as catalysts in biotechnology, for example to create chemical products such as pharmaceutics. Researchers now identified an enzyme that, when illuminated with blue light, becomes catalytically active and initiates a reaction that was previously unknown in enzymatics. The study was published in "Nature Communications".

Enzymes: they are the central drivers for biochemical metabolic processes in every living cell, enabling reactions to take place efficiently. It is this very...

Im Focus: New double-contrast technique picks up small tumors on MRI

Early detection of tumors is extremely important in treating cancer. A new technique developed by researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from normal tissue. The work is published May 25 in the journal Nature Nanotechnology.

researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from...

Im Focus: I-call - When microimplants communicate with each other / Innovation driver digitization - "Smart Health“

Microelectronics as a key technology enables numerous innovations in the field of intelligent medical technology. The Fraunhofer Institute for Biomedical Engineering IBMT coordinates the BMBF cooperative project "I-call" realizing the first electronic system for ultrasound-based, safe and interference-resistant data transmission between implants in the human body.

When microelectronic systems are used for medical applications, they have to meet high requirements in terms of biocompatibility, reliability, energy...

Im Focus: When predictions of theoretical chemists become reality

Thomas Heine, Professor of Theoretical Chemistry at TU Dresden, together with his team, first predicted a topological 2D polymer in 2019. Only one year later, an international team led by Italian researchers was able to synthesize these materials and experimentally prove their topological properties. For the renowned journal Nature Materials, this was the occasion to invite Thomas Heine to a News and Views article, which was published this week. Under the title "Making 2D Topological Polymers a reality" Prof. Heine describes how his theory became a reality.

Ultrathin materials are extremely interesting as building blocks for next generation nano electronic devices, as it is much easier to make circuits and other...

Im Focus: Rolling into the deep

Scientists took a leukocyte as the blueprint and developed a microrobot that has the size, shape and moving capabilities of a white blood cell. Simulating a blood vessel in a laboratory setting, they succeeded in magnetically navigating the ball-shaped microroller through this dynamic and dense environment. The drug-delivery vehicle withstood the simulated blood flow, pushing the developments in targeted drug delivery a step further: inside the body, there is no better access route to all tissues and organs than the circulatory system. A robot that could actually travel through this finely woven web would revolutionize the minimally-invasive treatment of illnesses.

A team of scientists from the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart invented a tiny microrobot that resembles a white blood cell...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

International Coral Reef Symposium in Bremen Postponed by a Year

06.04.2020 | Event News

 
Latest News

Black nitrogen: Bayreuth researchers discover new high-pressure material and solve a puzzle of the periodic table

29.05.2020 | Materials Sciences

Argonne researchers create active material out of microscopic spinning particles

29.05.2020 | Materials Sciences

Smart windows that self-illuminate on rainy days

29.05.2020 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>