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 Perovskite-silicon solar cell research collaboration hits 25.2% efficiency
15.06.2018 | Helmholtz-Zentrum Berlin für Materialien und Energie GmbH

nachricht Second heat source optimises heat pump system
12.06.2018 | FIZ Karlsruhe – Leibniz-Institut für Informationsinfrastruktur GmbH

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: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Carbon nanotube optics provide optical-based quantum cryptography and quantum computing

19.06.2018 | Physics and Astronomy

How to track and trace a protein: Nanosensors monitor intracellular deliveries

19.06.2018 | Life Sciences

New material for splitting water

19.06.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>