What’s New

The MAST Upgrade vacuum vessel is getting a paint job — and its new look will ensure the experiment produces top-quality plasma physics data when it starts operating next year.

While it's a shame to cover up the gleaming stainless steel surfaces, science must take precedence over aesthetic considerations. A number of key measuring systems — diagnostics — on MAST-U will rely on accurate readings of light from the plasma. With uncovered steel, the light bounces off the vessel surfaces, playing havoc with the measurements. Reflected light also makes it more difficult to examine images of the plasma for physics phenomena such as ELM instabilities. Applying graphite-based paint to the walls greatly reduces these reflections, giving physicists much better results to work with.

Read the whole article at CCFE.

The delegation from the Chinese Ministry of Science & Technology (MOST) that was received at ITER on 26 January also paid a visit to the International School in the neighbouring town of Manosque. Headed by Luo Delong, head of the Chinese Domestic Agency for ITER, and Sun Yuming, Deputy Director-General of the Executive Office at MOST, the delegation had a gift for the students in the Chinese section: four boxes of textbooks for primary school classes and picture books for pre-schoolers.

Of the 34 students in the Chinese section 21 are "ITER children"; the others are French nationals learning Chinese as second foreign language.

One of the biggest obstacles to making fusion power practical—and realizing its promise of virtually limitless and relatively clean energy—has been that computer models have been unable to predict how the hot, electrically charged gas inside a fusion reactor behaves under the intense heat and pressure required to make atoms stick together.

The key to making fusion work—that is, getting atoms of a heavy form of hydrogen called deuterium to stick together to form helium, releasing a huge amount of energy in the process—is to maintain a sufficiently high temperature and pressure to enable the atoms overcome their resistance to each other. But various kinds of turbulence can stir up this hot soup of particles and dissipate some of the intense heat, and a major problem has been to understand and predict exactly how this turbulence works, and thus how to overcome it.

A long-standing discrepancy between predictions and observed results in test reactors has been called "the great unsolved problem" in understanding the turbulence that leads to a loss of heat in fusion reactors. Solving this discrepancy is critical for predicting the performance of new fusion reactors such as the huge international collaborative project called ITER, under construction in France.

Now, researchers at MIT's Plasma Science and Fusion Center, in collaboration with others at the University of California at San Diego, General Atomics, and the Princeton Plasma Physics Laboratory, say that they have found the key. In a result so surprising that the researchers themselves found it hard to believe their own results at first, it turns out that interactions between turbulence at the tiniest scale, that of electrons, and turbulence at a scale 60 times larger, that of ions, can account for the mysterious mismatch between theory and experimental results.

The new findings are detailed in a pair of papers published in the journals Nuclear Fusion and AIP Physics of Plasmas, by MIT research scientist Nathan Howard, doctoral student Juan Ruiz Ruiz, Cecil and Ida Green Associate Professor in Engineering Anne White, and 12 collaborators.

See the original story on MIT News.

Photo courtesy of the researchers.

The Kudowa Summer School "Towards Fusion Energy" takes place every two years in Kudowa Zdrój, Poland.

Organized by the Institute of Plasma Physics and Laser Microfusion (IPPLM) and the International Centre for Dense Magnetised Plasma (ICDMP), the summer program is geared toward a multinational audience, principally PhD students but also Master's students and young scientists from all over Europe.

Courses focus on various aspects of fusion energy, plasma experiments, plasma modelling and technology for young scientists from different countries. The subject of the Kudowa Summer School in 2016 is: Power Exhaust in Fusion Plasmas.

The 2016 Kudowa Summer School will take place from 13 to 17 June 2016 (registration deadline 20 March). For more information, visit the dedicated website.