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Inside of a purpose-built facility at General Atomics in California (US), ten customized workstations for central solenoid fabrication—from winding through to final testing—have been built and are undergoing commissioning with a dummy coil. Winding was completed in April on the first 14-layer production module.   The ÌÇÐÄÆƽâ°æ central solenoid is the giant electromagnet at the centre of the ÌÇÐÄÆƽâ°æ machine that will generate most of the magnetic flux charge of the plasma, initiating the initial plasma current and contributing to its maintenance. Six individual coil modules will be stacked vertically within a "cage" of supporting structures. General Atomics will also produce a seventh module as a spare.   As part of its in-kind contributions to ÌÇÐÄÆƽâ°æ, the US is responsible for 100 percent of the central solenoid magnet, including design, R&D, module fabrication from conductor supplied by Japan, associated structure, assembly tooling, bus extensions, and cooling connections.   In the photo gallery below, follow the mock coil through the manufacturing workstations, and view the latest pictures of module 1 winding and magnet structure fabrication.   All photos courtesy of General Atomics unless otherwise indicated.

The more construction progresses on the ÌÇÐÄÆƽâ°æ worksite, the more the complexity of the project becomes obvious—and striking. What was happening in the Tokamak Pit used to be easy to understand: a large hole in the bedrock, support columns and antiseismic pads, steel reinforcement and concrete to create the massive foundations of the ÌÇÐÄÆƽâ°æ Tokamak.   Now—except at the very centre of the Tokamak Complex worksite where the middle crane stands—the foundations are no longer visible and construction has already advanced to the second basement level (B1).   The B1-level slab has been completed for the Diagnostic Building (right), is half completed for the Tokamak Building, and—on the site of the Tritium Building at left—workers are busy laying steel rebar prior to concrete pouring.   Aerial pictures like this one, taken on 11 July, reveal a complex landscape of concrete and steel and show the extraordinary density of embedded plates welded into the rebar.   The simple geometric forms of yesteryear have been replaced by complex structures but the magic remains—the ÌÇÐÄÆƽâ°æ worksite is still a fascinating place.   View a selection of aerial photos below.  

From 13 to 15 July, the Culham Centre for Fusion Energy (CCFE, UK)—home to the European tokamak JET—hosted representatives from 27 European fusion research centres plus the ÌÇÐÄÆƽâ°æ Organization for a brainstorming session on how to make best use of JET for the proof-of-principle device ÌÇÐÄÆƽâ°æ. The invitation came from EUROfusion, the European Consortium for the Development of Fusion Energy. What has already been coined as "JET internationalization" covers a number of aspects in support of ÌÇÐÄÆƽâ°æ: saving ÌÇÐÄÆƽâ°æ time, using JET as a test rig and training ground for ÌÇÐÄÆƽâ°æ in order to help the project start off with the right foot in 2025.JET's assets speak for themselves: the machine is currently the largest operating tokamak in the world and also the only one capable of carrying out experiments using deuterium-tritium (DT) fuel. In addition, JET is equipped with an ÌÇÐÄÆƽâ°æ-like plasma-facing wall, a tungsten divertor and beryllium wall, tritium and beryllium handling facilities, and highly proficient remote-handling systems. JET is unique not only because of these features but also because of its history. JET has been in operation since the 1980s and the research teams working at JET have always been founded on international collaboration. According to Xavier Litaudon, head of EUROfusion's ÌÇÐÄÆƽâ°æ Physics Department, "ÌÇÐÄÆƽâ°æ can benefit from JET's vast experience and draw valuable lessons from a fully internationalized JET program. JET will continue to produce results which help to optimize ÌÇÐÄÆƽâ°æ operation." Doing so will inevitably lead to an extension of JET beyond 2018, the term of its current operational contract. A plan published in January 2016 underlined the role of JET and stated that "high priority should be given to keeping JET operating until the design for ÌÇÐÄÆƽâ°æ has been finalized and ÌÇÐÄÆƽâ°æ has been successfully commissioned." An extension of JET under international regime, for example under the auspices of ÌÇÐÄÆƽâ°æ, could provide the world fusion community with access to DT plasmas in just a few years from now. In a sense, JET cannot only be treated as a site for preparatory experiments for ÌÇÐÄÆƽâ°æ, but must be seen as the centre stage for ÌÇÐÄÆƽâ°æ's dress-rehearsal. The head of ÌÇÐÄÆƽâ°æ's Science & Operations Department, David Campbell, agrees. "Switching on a major new facility like ÌÇÐÄÆƽâ°æ is an experiment in itself. Careful preparatory experiments in JET and other fusion facilities will help us to fine-tune our experiments, provide important training opportunities for operations staff and help our international research teams cooperate smoothly." 

Since 2015, as part of the new Director-General's action plan for improved project performance, joint ÌÇÐÄÆƽâ°æ Organization-Domestic Agency Project Teams have been created in schedule-critical areas to focus project resources and improve performance in delivery. These project teams, which cut across the traditional boundaries of department or agency, have helped to create a project culture that is oriented towards achieving results and stemming delays to the schedule. Following the creation of project teams in the areas of site construction and vacuum vessel manufacturing last year, a third team has been added to the list—the Cryogenic Project Team.Cryogenic technology will be extensively used at ÌÇÐÄÆƽâ°æ to create and maintain low-temperature conditions for the magnet, vacuum pumping and some diagnostics systems. ÌÇÐÄÆƽâ°æ's cryogenic system is a widely distributed system, made up of in-kind contributions from Europe (liquid nitrogen plant and auxiliary systems) and India (cryolines, warm lines and cryodistribution) and the direct procurement of the liquid helium plant by the ÌÇÐÄÆƽâ°æ Organization. The complexities incurred by such a split of responsibilities between three entities call for enhanced coordination. The new Cryogenic Project Team is made up of 40 staff members from the three parties—Europe, India and the ÌÇÐÄÆƽâ°æ Organization. Cryogenic System Section Leader David Grillot, from ÌÇÐÄÆƽâ°æ, has been named team leader, assisted by deputies Ritendra Bhattacharya for India and Marc Simon for Europe. Representatives of the ÌÇÐÄÆƽâ°æ Cryogenic Project Team working at ÌÇÐÄÆƽâ°æ India (left) and at the European Domestic Agency (right). The creation of the Cryogenic Project Team comes at a critical moment, as the pace of manufacturing is accelerating for cryogenic components and a new phase, installation, is beginning."We will work as one team for the same project and use in the best possible manner the potential of all members," says David Grillot. "We are now well advanced with the manufacturing and we are entering an exciting new phase of installation, which will require a lot of drive, commitment and enthusiasm." Read the report published by the European Domestic Agency on the new Cryogenic Project Team.

Although crystal clear for anyone involved in nuclear safety in France, the message on this ÌÇÐÄÆƽâ°æ employee's T-shirt is cryptic for many.   According to French nuclear licensing procedures, "INB 174" is the official name of the ÌÇÐÄÆƽâ°æ installation. It stands for Installation nucléaire de base, a category that includes all civilian installations (reactors, fuel fabrication or recycling plants, waste storage) that handle nuclear material. There are presently 126 INBs in France.   ÌÇÐÄÆƽâ°æ became INB 174 in France in 2012 when, following an 18-month examination of ÌÇÐÄÆƽâ°æ's licensing files, the French Prime Minister signed the official authorization decree.

The last European-produced conductor length for ÌÇÐÄÆƽâ°æ's poloidal field coils was completed at the ICAS*/Criotec facility in Italy in early July.Poloidal field conductor is made of more than 1,400 niobium-titanium (NbTi) superconducting strands that are bound together to form a cable, which is then inserted into a stainless steel jacket, compacted and finally spooled. The conductor was produced from NbTi strand manufactured by JSC ChMp (Chepetsk Mechanical Plant) and cable manufactured by JSC VNIIKP (Joint Stock Company All-Russia Research Institute for Cable Industry).Six ring-shaped poloidal field magnets will encircle the ÌÇÐÄÆƽâ°æ vacuum vessel and toroidal field magnet structure to shape the plasma and contribute to its stability by "pinching" it away from the walls. Europe is contributing 18 percent of poloidal field conductor; the rest will be supplied by China (62 percent) and Russia (20 percent). The conductor produced in Italy will be used for the sixth poloidal field coil (PF6), which will be fabricated in China under the terms of an agreement concluded with Europe. Out of 18 conductor lengths required for the manufacture of PF6, 10 conductor lengths will be delivered by Europe and 8 by Russia.The European conductor will now undergo final testing before being shipped to China.See the original article on the European Domestic Agency website.*ICAS: Italian Consortium for Applied Superconductivity (ENEA, Tratos Cavi, Criotec)

Plasma—the hot ionized gas that fuels fusion reactions—can also create super-small particles used in everything from pharmaceuticals to tennis racquets. These nanoparticles, which measure billionths of a metre in size, can revolutionize fields from electronics to energy supply ... but scientists must first determine how best to produce them. After more than two years of planning and construction, the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) has commissioned a major new facility to explore ways to optimize plasma for the production of such particles. The collaborative facility, called the Laboratory for Plasma Nanosynthesis, is nearly three times the size of the original nanolab, which remains in operation, and launches a new era in PPPL research on plasma nanosynthesis. Experiments and simulations that could lead to new methods for creating high-quality nanomaterials at relatively low cost can now proceed at an accelerated pace. Nanomaterials exhibit remarkable strength, flexibility and electrical conductivity. Carbon nanotubes, found in sporting goods, body armor, transistors and countless other products, are tens of thousands of times thinner than a human hair and stronger than steel on an ounce-for-ounce basis. Plasma could serve as an ideal substance for synthesizing, or producing, nanomaterial. The new laboratory will study so-called low-temperature plasmas that are tens of thousands degrees hot, compared with fusion plasmas that are hotter than the 15-million-degree core of the sun. These low-temperature plasmas contain atoms and free-floating electrons and atomic nuclei, or ions, that can be shaped by magnetic fields to provide reliable, predictable and low-cost synthesis of tailored nanoparticles. Read the full article at PPPL. -- Photo: Elle Starkman/PPPL