New imaging technique provides improved insight into controlling the plasma in fusion experiments

Jul 10, 2013 by John Greenwald
New imaging technique provides improved insight into controlling the plasma in fusion experiments
Graphic representation of 2D images of fluctuating electron temperatures in a cross-section of a confined fusion plasma. Credit: Plasma Physics and Controlled Fusion

A key issue for the development of fusion energy to generate electricity is the ability to confine the superhot, charged plasma gas that fuels fusion reactions in magnetic devices called tokamaks. This gas is subject to instabilities that cause it to leak from the magnetic fields and halt fusion reactions.

Now a recently developed imaging can help researchers improve their control of instabilities. The new technique, developed by physicists at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL), the University of California-Davis and General Atomics in San Diego, provides new insight into how the instabilities respond to externally applied magnetic fields.

This technique, called Electron Cyclotron Emission Imaging (ECEI) and successfully tested on the DIII-D tokamak at General Atomics, uses an array of detectors to produce a 2D profile of fluctuating electron temperatures within the . Standard methods for diagnosing plasma temperature have long relied on a single line of sight, providing only a 1D profile. Results of the ECEI technique, recently reported in the journal Plasma Physics and Controlled Fusion, could enable researchers to better model the response of confined plasma to external magnetic perturbations that are applied to improve plasma stability and performance.

Explore further: Optimum inertial self-propulsion design for snowman-like nanorobot

More information: Tobias, B. et al. 2013. Boundary perturbations coupled to core 3/2 tearing modes on the DIII-D tokamak, Plasma Physics and Controlled Fusion. Article first published online: July 5, 2013. DOI:10.1088/0741-3335/55/9/095006

add to favorites email to friend print save as pdf

Related Stories

With lithium, more is definitely better

Nov 10, 2011

A team of scientists working at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) has found that increasing the amount of lithium coating in the wall of an experimental fusion reactor ...

One step closer to controlling nuclear fusion

Jan 13, 2012

Using a heating system, physicists have succeeded for the first time in preventing the development of instabilities in an efficient alternative way relevant to a future nuclear fusion reactor. It’s an ...

A new spin on understanding plasma confinement

Nov 10, 2011

To achieve nuclear fusion for practical energy production, scientists often use magnetic fields to confine plasma. This creates a magnetic (or more precisely "magneto-hydrodynamic") fluid in which plasma is tied to magnetic ...

Catching tokamak fastballs: Controlling runaway electrons

Nov 11, 2011

a leading design concept for producing nuclear fusion energy—can, under certain rare fault conditions, produce beams of very energetic "runaway" electrons that have the potential to damage interior surfaces ...

Recommended for you

Mapping the optimal route between two quantum states

10 hours ago

As a quantum state collapses from a quantum superposition to a classical state or a different superposition, it will follow a path known as a quantum trajectory. For each start and end state there is an optimal ...

Spin-based electronics: New material successfully tested

15 hours ago

Spintronics is an emerging field of electronics, where devices work by manipulating the spin of electrons rather than the current generated by their motion. This field can offer significant advantages to computer technology. ...

Verifying the future of quantum computing

16 hours ago

Physicists are one step closer to proving the reliability of a quantum computer – a machine which promises to revolutionise the way we trade over the internet and provide new tools to perform powerful simulations.

A transistor-like amplifier for single photons

Jul 29, 2014

Data transmission over long distances usually utilizes optical techniques via glass fibres – this ensures high speed transmission combined with low power dissipation of the signal. For quite some years ...

User comments : 0