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In a tokamak reactor, the plasma periphery (also called the scrape-off layer or SOL) is the critical buffer region between the hot core and the solid wall elements.   It is the region in which plasma must be cooled sufficiently for technologically feasible wall armour components to be deployed and is the vehicle through which particles escaping the core are exhausted. Without such exhaust, the helium ash produced by the deuterium-tritium fusion reactions would pollute the core plasma and prevent burn sustainment.   Most currently operating devices and all future reactor concepts based on the tokamak—including °ÄÃÅÁùºÏ²Ê¸ßÊÖ—use magnetic fields to divert the SOL plasma to the divertor region where the cooling action and particle exhaust can be more readily managed. This also has the effect of reducing the penetration of impurity particles (released from plasma-facing materials into the core), thereby preventing the degradation of plasma purity.   When seeking to understand the behaviour of the SOL, it is important to take into consideration its interaction with materials and the presence of very low plasma temperatures in comparison to the hot core plasma. A complete model thus requires the introduction of surface physics processes and atomic physics in addition to the usual plethora of plasma transport mechanisms. This rich and complex array of phenomena requires the use of specialized computer simulation tools.   Following a series of tutorial presentations on the first day of workshop, the participants learned how to import SOLPS-°ÄÃÅÁùºÏ²Ê¸ßÊÖ from the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization GIT repository and succeeded in compiling the code on their home institution computers. They were then taken step-by-step through the complex process of building a simulation grid for a real tokamak simulation (in this case an example from the C-Mod device at MIT) which, with its high plasma density and magnetic field, has a divertor plasma most closely resembling today the conditions expected in °ÄÃÅÁùºÏ²Ê¸ßÊÖ. One such tool, used at °ÄÃÅÁùºÏ²Ê¸ßÊÖ since the days of the Engineering Design Activities (EDA) in the early 1990s, is the SOLPS (SOL Plasma Simulation) suite, previously known as B2-Eirene. It has been the workhorse for the design of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ divertor and was the principal tool with which the °ÄÃÅÁùºÏ²Ê¸ßÊÖ fuelling and pumping requirements were established. The code package is still intensively employed to study °ÄÃÅÁùºÏ²Ê¸ßÊÖ plasma boundary physics and tokamak performance.   Over the years, SOLPS has been used and developed in parallel by various research groups around the world, most notably at the Max Planck Institute for Plasma Physics IPP Garching (Germany), St. Petersburg State Polytechnical University (Russia), Forschungszentrum Jülich (Germany) and, of course, at °ÄÃÅÁùºÏ²Ê¸ßÊÖ.   As early as 2009, it was decided that the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization should upgrade the code version it used and provide a new, more versatile package for °ÄÃÅÁùºÏ²Ê¸ßÊÖ simulations by merging the most recent developments made by the SOLPS community from a physics and a numerical point of view. This new code suite is named SOLPS-°ÄÃÅÁùºÏ²Ê¸ßÊÖ and it will be one of the first major components to be incorporated within °ÄÃÅÁùºÏ²Ê¸ßÊÖ's Integrated Modelling & Analysis Suite (IMAS), a framework to support the development of sophisticated modelling workflows for °ÄÃÅÁùºÏ²Ê¸ßÊÖ.   An important milestone in this effort was reached last week with the official launch of SOLPS-°ÄÃÅÁùºÏ²Ê¸ßÊÖ. Users and developers of former SOLPS versions, representing six of the seven °ÄÃÅÁùºÏ²Ê¸ßÊÖ Members, converged on the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Headquarters for a dedicated code release workshop—the largest such gathering of SOLPS users ever staged.   Over an intense five days, participants learned about the new features of SOLPS-°ÄÃÅÁùºÏ²Ê¸ßÊÖ and how to run the suite and interpret its results. They were introduced, through hands-on tutorials given by Simon Pinches and Louwrens Van Dellen of °ÄÃÅÁùºÏ²Ê¸ßÊÖ's Confinement and Modelling Section, to the IMAS software management tools, including the GIT distributed revision control system and also saw how modified versions are automatically built and tested on the IMAS Continuous Integration server.  Discussions also took place on future directions for the code, such as new physics phenomena to be added, advanced numerical schemes to implement, and user interfaces and archival/retrieval tools.   Further training sessions are planned at selected °ÄÃÅÁùºÏ²Ê¸ßÊÖ Member institutions for those who were unable to attend this launch workshop.  With the upgraded package now launched, the hope is that the code will be used as widely as possible to simulate plasma experiments throughout the °ÄÃÅÁùºÏ²Ê¸ßÊÖ community, helping to improve confidence in and further improve this key simulation tool.   For further information, please contact @email.

°ÄÃÅÁùºÏ²Ê¸ßÊÖ Director-General Bernard Bigot recently spent a full four days in Korea, where he discussed project status with the Korean Domestic Agency, met industrial suppliers, and held a bilateral meeting with government representative Minister Choi Yang-hee of the Ministry of Science, ICT and Future Planning (MSIP).   On 13 April, the Director-General visited Korea's National Fusion Research Institute (NFRI) and celebrated the extension of the Memorandum of Understanding for technical cooperation between NFRI and the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization. His visit was also the occasion to conclude an agreement on the procurement of Test Blanket System connection pipes—these pipes, which are part of the Members' Test Blanket Systems, will be procured in group by °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization as a cost-saving measure.   Director-General Bigot visited the KSTAR tokamak facility for the first time in the company of Yang Hyung-yeol, head of the Advanced Engineering Research Department. "I am very impressed to be here," the Director-General said during the tour. "KSTAR has been addressing many nuclear fusion issues that are important to °ÄÃÅÁùºÏ²Ê¸ßÊÖ. Therefore, I would like to ask all of you to carry out your given missions faithfully."   °ÄÃÅÁùºÏ²Ê¸ßÊÖ Korea recently held its 2015 kick-off meeting, with the attendance of the fusion R&D support team from MSIP, and confirmed the work plan for the year. He also met with Korean industrial suppliers Hyundai Heavy industry (vacuum vessel) and SFA Engineering (assembly tooling, thermal shield), and had the chance to visit Dawonsys (AC/DC converters) and KEPCO E&C (engineering support). "Meeting the industrial suppliers was an excellent opportunity to verify the manufacturing status of procurement items in the field and to see, first hand, the technological competitiveness of Korean enterprises that are procuring items for °ÄÃÅÁùºÏ²Ê¸ßÊÖ."   In his meeting with Minister Choi, Director-General Bigot expressed his appreciation for Korea's strong participation in °ÄÃÅÁùºÏ²Ê¸ßÊÖ and asked for the government's continued interest and cooperation. Minister Choi re-confirmed his support for the project and his confidence in the strong leadership that has been put in place.

Same component, same origin, same route: the second of four high voltage transformers procured by the US and manufactured in Korea reached Marseille's industrial port (Fos-sur-Mer) on Sunday 19 April. The 87-ton component was unloaded the following morning and placed in storage, where it will remain until the last two transformers reach Fos (delivery expected around 10 May). On the °ÄÃÅÁùºÏ²Ê¸ßÊÖ platform, near the 400 kV switchyard, workers are putting the finishing touches to the large concrete pit that will host the first transformer, which should be operational in the early months of 2016. Connected to the switchyard, it will bring down the voltage to 22 kV and dispatch power to the various plant systems of the installation.  

​An important milestone has been reached on the MAST-Upgrade project, with the re-installation of four of the largest magnetic coils inside the machine. Many of the internal poloidal field magnetic coils are new, especially around the upper and lower parts of the device. Only four coils in MAST-Upgrade remain from the original MAST experiment — the large mid-plane P4 and P5 (upper and lower) coils. But it was not as simple as just leaving them in the vessel — they were removed with all the other internal equipment to enable the interior to be fully stripped down and cleaned. The coils were also comprehensively cleaned, including a hydroblast pressure wash. The P5 coils were then fitted with new flux loops. Prior to re-installation, a full spatial survey of the vessel and coil supports and indeed of the shape of the coils themselves was undertaken. All four cleaned and surveyed coils were re-installed a few weeks ahead of schedule, on new strengthened coil supports inside the MAST-U vessel. A final survey indicated they were within 0.5mm of their optimum position — minimizing any stray fields when operations commence. Coil re-installation is an important step, marking in many ways the beginning of the rebuild of the tokamak.

​The Ecole Polytechnique Fédérale de Lausanne (EPFL) is presenting the first Massive Open Online Course (MOOC) on plasma physics and its applications, including fusion energy, astrophysical and space plasmas, societal and industrial applications. Enroll now ! A team including Prof. A. Fasoli, Prof. P. Ricci and colleagues at the Plasma Physics Research Center (CRPP) of EPFL, recorded the first MOOC on the basics of plasma physics and its main applications. Current titles include:• Basics of plasma physics• Basics of space plasmas in astrophysics• Industrial and medical applications of plasmas• Basics of fusion as a sustainable energy• Advanced concepts in fusion such as magnetic confinement, plasma heating and energy extraction. Classes start on 1 May 2015. The course is given in English and will last nine weeks. Register or get more information here or view the course introduction on YouTube.

​The mission of the JT-60SA tokamak (based in Naka, Japan, and financed jointly by Europe and Japan) is to contribute to the early realization of fusion energy by addressing key physics issues for °ÄÃÅÁùºÏ²Ê¸ßÊÖ and DEMO. It is a fully superconducting tokamak capable of confining high-temperature (100 million degree) deuterium plasmas, equivalent to achieving plasma energy balance if 50/50 deuterium/tritium were used. It is designed to help optimise the plasma configurations for °ÄÃÅÁùºÏ²Ê¸ßÊÖ and DEMO, and has a large amount of power available for plasma heating and current drive, from both positive and negative ion neutral beams, as well as electron cyclotron resonance radio-frequency heating. The machine will be able to explore full non-inductive steady-state operation. More news in the March issue of the JT-60 SA newsletter.