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High Temperature Superconductor (HTS) current leads are key components of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ magnet system, transferring large current from room-temperature power supplies to very low-temperature superconducting coils at minimal heat load to the cryogenic system. The HTS current leads for the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Tokamak are procured by the Chinese Domestic Agency through the Institute of Plasma Physics (ASIPP) in Hefei, China. Current leads are key magnet components, transferring large current from room-temperature power supplies to very low-temperature superconducting coils. Following the signature of the Feeder Procurement Arrangement in January 2011, ASIPP launched a string of activities to prepare for series production. These included the qualification of critical manufacturing technologies through targeted trials in mockups, which will conclude with the manufacturing and testing of several pairs of current lead prototypes this year.   Just in time for the Chinese New Year festivities, ASIPP successfully completed the test of a pair of correction coil 10 kA current lead prototypes. Many things had to fall in place to make this test possible. First ASIPP (under the leadership of Tingzhi Zhou) and its supplier Keye had to deliver the correction coil leads on schedule. Second, a large test facility—capable of testing the coil leads as well as other °ÄÃÅÁùºÏ²Ê¸ßÊÖ components such as the correction coils and feeders—needed to be built and commissioned.   The °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization contributed to the test with the delivery of a turn-key control system, complete with critical quench detection and interlock functions. °ÄÃÅÁùºÏ²Ê¸ßÊÖ's Coil Power Supply Section also contributed by delivering a set of flexible copper busbars. These contributions are in fact prototypes of systems that are being procured for the °ÄÃÅÁùºÏ²Ê¸ßÊÖ machine, and for which tests in a machine-relevant environment are important steps in their development.   After two long weeks of testing, ASIPP's Kaizhong Ding thanked not only the test team for its hard work, but also acknowledged the valuable support provided by °ÄÃÅÁùºÏ²Ê¸ßÊÖ's control, magnet and power supply teams that, in the end, allowed these tests to run smoothly and be completed in time for a well-deserved rest over the Chinese New Year holiday.    Toroidal field and poloidal field/central solenoid prototype leads are now in final stages of manufacturing and test results will be reported in Newsline soon.

The European Domestic Agency has signed a contract for the manufacturing of the CER diagnostic coil system, an important milestone on the road to supplying 25 percent of the diagnostic systems required for °ÄÃÅÁùºÏ²Ê¸ßÊÖ. A CER coil (for Continuous External Rogowski) is an inductive sensor designed to measure the toroidal current flowing within the contour of the toroidal field coils, which approximates to the plasma current under steady conditions—making it a key measurement with relevance for safety and plasma control. CER coils, measuring approximately 50 metres in length, will be located within the casings of three toroidal field coils. The diagnostic coils are formed from two layers of concentric windings, insulated by fibreglass, and enclosed in a stainless steel braided sheath. In contrast with other measurements of plasma current, the Rogowski method provides the measurement with a single sensor, resulting in very high reliability. This contract milestone follows design worked carried out under a grant awarded by the European Domestic Agency, successful prototype testing in 2011, and a successful Final Design Review in 2013. Two European companies have been selected: Axon (France), for the electrical aspects of the system; and Sgenia (Spain), for the mechanical aspects. A manufacturing readiness review meeting was held with the contractors in order to verify final preparations for manufacturing, which is expected to start in April. Walter Rogowski (May 7, 1881 — March 10, 1947) was a German physicist who bridged the gap between theoretical physics and applied technology in numerous areas of electronics. Read the full story on the European Domestic Agency website.

The number of visitors to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ site increases steadily from year to year, testimony of the public's strong interest in the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project. A total of 83,999 people have visited the site since 2008, 16,824 of them in 2014 (a 13.5 percent increase over 2013).   Visits are key to increasing public awareness about °ÄÃÅÁùºÏ²Ê¸ßÊÖ and establishing good relations with the surrounding community, institutions, industries and schools. Visits are organized by the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization visit team in close collaboration with Agence Iter France—the °ÄÃÅÁùºÏ²Ê¸ßÊÖ team manages visits for the general public, companies, international delegations, politicians and the media, while Agence °ÄÃÅÁùºÏ²Ê¸ßÊÖ France runs a dedicated program for school groups.   In 2014, 42 percent of all visitors were school children (just over 7,000 young visitors). Another 30 percent came from the "general public" (nearly 5,000 people), 15 percent from industry, 6 percent from universities, and the remainder (7 percent) from government and international institutions, the media, or °ÄÃÅÁùºÏ²Ê¸ßÊÖ Domestic Agencies.   Approximately one out of every six visits was "technical"—visitors with specialized interests who benefitted from presentations and a site tour led by °ÄÃÅÁùºÏ²Ê¸ßÊÖ staff from the technical divisions (buildings and construction, electrical, plasma science, etc.).   But °ÄÃÅÁùºÏ²Ê¸ßÊÖ scientists and engineers also appreciate the chance to exchange with the general public. For Joël Hourtoule, Electrical Power Distribution Section leader, "visits are the link between the engineers contributing to the project and the public. For an engineer, it is important to be able to explain what kind of works we are doing here and to get feedback from the public. It's always a good experience to meet the outside world and to answer the many questions they may have."   Visits also take place as part of technical working groups, that convene to work on specific issues. In that context, ''visits are a way to share experiences with technical staff from other industries. We share our experience, for example, in conception requirements and construction techniques within the framework of a nuclear facility,'' says Laurent Patisson, head of the Nuclear Buildings Section.   Interest remains high from university-level students studying fusion technology and engineering all around the world. "Giving talks to university students is the perfect way to show them what comes after they have completed their studies, and how to put theory into practice," says Laurent. Tom Farley, a PhD student in physics and an intern currently at CEA Cadarache, agrees: "It's a great chance that °ÄÃÅÁùºÏ²Ê¸ßÊÖ is open to the public. For students like me, catching a glimpse of this challenging project and meeting the staff working here is a unique opportunity to see what is happening behind the scenes. It gives me hope for the future and—who knows—I might apply for a position in the years to come!"

Arriving from Santander, Spain, the convoy passed the gate to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ storage area at the very moment the eclipse reached its maximum. As a dull, ashen light fell on the surrounding countryside, the truck and its load came to a halt—the first equipment procured by the European Domestic Agency had safely reached its destination. Representatives of the European Domestic Agency, °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization, and ENSA celebrating the arrival of the 20-tonne tank at the °ÄÃÅÁùºÏ²Ê¸ßÊÖ site. Manufactured by the Spanish company ENSA, the load consisted of a 20-tonne, 100 m³ tank destined for the °ÄÃÅÁùºÏ²Ê¸ßÊÖ detritiation system. It is one of two "emergency tanks" that will collect the tritiated water in case an abnormal situation develops during operations (the second will be delivered in April). The tank that was delivered on 20 March will be the first Safety Important Component to be installed in the Tokamak Complex. "The fact that the emergency tanks are being delivered now means that we will be able to install them before the next level is poured," explained Manfred Glugla, head of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Fuel Cycle Engineering Division.

Once a plasma enthusiast, always a plasma enthusiast... Jean Jacquinot, former director of JET and of the French CEA Research Department for Controlled Fusion (and now an advisor to °ÄÃÅÁùºÏ²Ê¸ßÊÖ Director-General Bernard Bigot) began his career in fusion in the mid-1960s. When he retired some forty years later he found himself a new passion: astrophotography. On Friday 20 March he took this striking image of our own familiar fusion furnace as it was partially obscured by the moon. (Note the small solar flare on the lower right of the Sun edge.)

​One of the biggest challenges facing fusion physicists is controlling the plasma inside a tokamak reactor.   Plasma — a gas of the fuels that are heated to start the fusion process — is difficult to keep stable, and seeks to escape the magnetic field that confines it within the machine. This results in 'instabilities' which make the plasma wobble and fluctuate, taking energy away from it and affecting the tokamak's performance.   Decades of research on tokamak experiments worldwide has led to a deep understanding of a myriad of different plasma instabilities with exotic names (from Edge Localised Modes to Tearing Modes, Kink instabilities and Sawteeth). Just as importantly, researchers are developing methods to stop them occurring, reduce their effect or stabilise them altogether.   Amongst all these challenges has been the fact that most of these instabilities, certainly those deep inside the plasma, are invisible to high-speed camera videos — until now, that is. University of York PhD student David Ryan is currently working at Culham Centre for Fusion Energy and he applied cutting-edge video magnification techniques to footage of plasmas in the MAST tokamak to see what would emerge.   Read more on CCFE website