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You're currently reading the news digest published from 29 December 2014 to 5 January 2015.
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A twice in a lifetime opportunity

One of the most important milestones in fusion history was achieved on 9 November 1991 when the European tokamak JET produced a significant amount of power for the first time from the fusion of deuterium and tritium nuclei. JET had achieved fusion with 10 percent tritium only. Two years later, the American TFTR, a tokamak of slightly smaller size, followed suit with a 50/50 deuterium-tritium (DT) mix. Throughout the 1990s, the two machines were to enter a "friendly competition" that culminated in 1997 with a record production of 16 MW at JET and, even more significant for the future of fusion, a series of 5-second, 4 MW stationary shots in H-mode that formed the basis for extrapolation to ITER.The year 1997 marked the end of the great DT adventure, however ... at least as concerns the 20th century—JET had completed its campaign and budgetary constraints in the US led to the dismantling of TFTR. No further campaign was planned, with the exception of an experiment with trace tritium at JET in 2003. The fusion community had glimpsed the Holy Grail; its members would have to wait for ITER to bring it home. But in 1997, ITER was still many years from realization ... "It's been almost 20 years. It was a fantastic experience and, at the time, I didn't think my generation would have another chance to participate in DT experiments," says Xavier Litaudon who, as a young physicist, was part of the 1997 campaign at JET. Litaudon, who until recently headed the Heating and Confinement Department at CEA's Institute for Magnetic Fusion Research (IRFM), is a lucky man. Not only will he soon have another shot at "real" fusion but he will manage the European participation and scientific exploitation of the 2017 DT campaign as head of the EUROfusion ITER Physics Department. (1) Since it entered operation in 1983, the European tokamak JET has always been at the heart of fusion research. Now, equipped with an ITER-like beryllium wall, an ITER-like tungsten divertor and upgraded heating systems, it is centre stage more than ever: "JET has become a much more ITER-like machine and will continue to provide answers to the big questions that are essential for ITER operation," he says. In July, the European Commission and the Culham Centre for Fusion Energy, signed a EUR 283 million contract that insures that JET will be financed until the end of 2018.   Meanwhile, at Tore Supra...   As JET is being readied for its 2017 deuterium-tritium campaign, the CEA superconducting tokamak Tore Supra (operated next door to ITER at CEA Cadarache) is undergoing major transformation to be used as a test bench for ITER.   Initiated in 2009, the WEST project (W Environment in Steady-state Tokamak, where "W" stands for tungsten) consists in replacing Tore Supra's carbon "limiter" with a tungsten divertor closely resembling ITER's, and in installing extra magnetic coils to confine the machine's originally circular plasma into an ITER-like "D-shaped" plasma.   This transformation will allow the upgraded 25-year-old tokamak (now part of EUROfusion's ITER Physics Programme) to test ITER-class, actively cooled divertor plasma-facing units. Like JET, Tore Supra will contribute to answering questions that are of vital importance for ITER. A first short-pulse experiment (~10 sec) is scheduled for early 2016 with a few ITER-like actively cooled sectors complemented by inertial cooled sectors made of graphite with tungsten coating.   Two years later, a second experimental campaign foresees an actively cooled divertor equipped with 456 ITER-like plasma-facing units. Throughout the summer holidays and well into October 2014, JET ran a series of experiments with deuterium plasmas, focusing on developing ITER-relevant plasma scenarios and addressing important ITER issues such as disruption mitigation and runaway electrons.The machine is now shut down and will restart in May 2015 to resume its scientific campaign in September with a refurbished ITER-like ion cyclotron resonance heating antenna and an optimized pellet injector (frozen deuterium pellets are injected into the plasma to mitigate instabilities known as ELMs). The "real thing" —implementing the actual fusion fuels deuterium and tritium—will only begin when all machine components have been commissioned, the operating scenario developed at full fusion performance, staff trained, safety measures checked and diagnostics systems adjusted. This will take the better part of two years. JET has changed a lot in 20 years, becoming more and more like ITER, and so has the world of fusion research. Fuelled by conceptual advances and the feedback from dozens of fusion machines, considerable progress has been made in understanding plasma behaviour and new "scenarios" have been developed, leading to better sustained plasma performance. (JET is collectively used by more than 350 scientists and engineers from all over Europe.) "We want to demonstrate that what we have observed with deuterium plasmas can be extrapolated to DT," says Litaudon. "We will be operating JET as if it were ITER. In that early phase, plasma current (~4 MA) and magnetic field (~4 Tesla) parameters will be comparable in both machines..." JET is the only operating machine licenced for tritium but it is not totally "ITER-like." Its smaller plasma volume (~ 100 m3 as compared to ITER's 840 m3) will limit fusion performance and its conventional (non-superconducting) coils and the fact that both its wall and divertor are not actively cooled will impact the duration of the plasma shots. However, the feedback from DT experiments in JET will be decisive for validating the ITER scenarios and readying the young generation of engineers and scientists for ITER operation. "It's a matter of time and money," says Xavier Litaudon. "If we gain one year on the learning curve, ITER can save a few hundred million euros..." (1) The JET Exploitation Manager, Lorne Horton, assisted by the JET Exploitation Unit, is responsible for implementing the JET operation contract on behalf of the Commission, including overseeing JET operation and ensuring consistency with the Fusion Roadmap.
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First ITER heavyweight reaches Fos-sur-Mer

Early on 19 December 2014, the vessel CMA CGM IVANHOE, loaded with some 10,000 containers, was pulled in by the small but powerful pilot boats and finally made fast at the Eurofos docks in Marseille's industrial harbour at Fos-sur-Mer.   One month before, the vessel had left the Hyundai docks in Ulsan, Korea with precious cargo on board—the first of four high voltage transformers for ITER's steady state electrical network.   Part of the US's 75 percent contribution to ITER's steady state electrical network, the transformers serve to connect the AC electrical distribution system to the 400kV grid operated by Réseau de Transport d'Electricité (RTE). They are being supplied under contract with Hyundai Heavy Industries, LLC in Korea.   In order to protect the component during its journey across the South China Sea, around the Cape of Good Hope and into Mediterranean waters, the transformer had been lashed down in one of the centre hatches where the ship's movement is weakest. It thus took a while for the transformer to emerge during unloading in Fos-sur-Mer. The 87-tonne transformer was lifted out of its "cabin" by gantry crane and loaded onto a waiting truck equipped with cantilever beams to secure the massive load.   The freight will remain in storage until 12 January 2015, when this first exceptional ITER convoy will slowly make its way along the ITER Itinerary towards the ITER site located some 100 kilometres to the north.
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ITER diagnostics poised to advance in the US

The US has made important progress recently in advancing contributions to ITER diagnostic systems. More than 40 diagnostic instruments will be installed on ITER to provide detailed information about the plasmas, allowing the operators to optimize the machine's performance and meet ITER's goals. All ITER Members are supplying diagnostics to the project; the US is designing seven instruments plus four port plugs, which will provide shielded housing for the diagnostics. Contributions include x-ray, laser, microwave and optical systems. As of late October, eleven Procurement Arrangements had been signed with the ITER Organization detailing the design, procurement and delivery responsibilities for the US. Four support contracts were placed in 2014 to advance designs, and one instrument is already in the final design phase. The US ITER diagnostics team is based at the Princeton Plasma Physics Laboratory and works closely with the US ITER project office managed by the Oak Ridge National Laboratory. "Plasma diagnostics has historically been an area of US strength, and we are home to some of the inventors of diagnostic techniques appropriate for ITER," said David Johnson, team leader for US ITER diagnostics and principal research physicist at PPPL. General Atomics and UCLA (University of California, Los Angeles) are leading the physics design for the low-field-side reflectometer, which will provide primary measurement of the electron density spatial profile in the outer edge of the plasma. This diagnostic also contributes to determining the plasma pressure gradient that influences plasma stability and energy transport. ORNL is developing the transmission line components needed for this instrument. Palomar Scientific Instruments joins General Atomics and UCLA under contract to develop the physics design for the toroidal interferometer-polarimeter. This instrument, which determines the electron density by probing the plasma with a carbon dioxide laser, will be used as a sensor in a feedback system to control various fueling sources. The diagnostic residual gas analyzer is now in final design at ORNL. Photo: US ITER/ORNL The electron cyclotron emission radiometer measures the spatial profile of the electron temperature in the plasma, a fundamental parameter for plasma behavior. The instrument provides time resolution adequate to serve in a feedback loop to stabilize predicted modes in the plasma. Three universities—University of Texas at Austin, University of Maryland and the Massachusetts Institute of Technology—are jointly developing the physics design, a calibration source, microwave sensors and analysis software.Infrared and visible cameras for viewing inside the ITER Tokamak chamber are now being developed by General Atomics, Lawrence Livermore National Laboratory and TNO, a Dutch laboratory for applied scientific research. This diagnostic will be used to look for parts of the ITER divertor region that are overheating.Oak Ridge National Laboratory is developing the residual gas analyzer. Now in final design, the instrument will measure the concentrations of neutral gases during a plasma discharge in the divertor exhaust duct and in the main chamber of the ITER Tokamak.The recently signed Procurement Arrangements cover two additional instruments. Experts at PPPL will develop the core imaging x-ray spectrometer, which will measure the plasma ion temperature and rotation. US ITER is targeting late 2015 for award of a contract for the motional Stark effect diagnostic instrument, which will measure the spatial profile of the current flowing in the plasma.In addition to diagnostic instruments, US ITER will also provide design, fabrication, assembly and testing of four diagnostic port plugs. The instruments view the plasma through labyrinths in these plugs, which also serve as radiation shields for the device. The PPPL team is leading the port plug design and integration effort. Because of the harsh environment inside the vacuum vessel, the instrument systems must cope with a range of conditions not previously encountered by diagnostic technology, all while performing with high reliability. The US ITER team is also supporting the integration of multiple diagnostics into these plugs, including some from other ITER partners.
Of interest

Now on show: the ITER absolute valve

https://www.iter.org/of-interest?id=418
Visitors coming to the ITER site will from now on have one more attraction to discover: The mock-up of an ITER absolute valve seal and test rig, used to demonstrate the feasibility of the largest high pressure, all-metal valve, ever to be manufactured.   ITER will rely on two very powerful neutral beam injectors to heat the plasma to fusion temperatures. A third injector will also be installed—the diagnostic neutral beam injector—which is used as a diagnostic for the plasma.   Each injector contains a vacuum vessel which needs to be vented to atmospheric pressure independently from the torus vacuum vessel in case of an incident. An absolute valve has thus been developed by the Swiss company VAT to "absolutely" isolate the vacuum in the torus from the neutral beam vacuum systems.   The valve uses seals made of stainless steel with silver coating to ensure high vacuum tightness up to a pressure differential of 0.1 MPa across the plate while maintaining a leak rate of less than 1·10-8 Pa·m3/s 1, but can withstand up to 0.2 MPa without incurring damage. With a nominal bore dimension of 1600 mm this absolute valve will be the largest ever manufactured, approximately five times bigger than existing products.

December 2014 issue of Fusion in Europe

https://www.iter.org/of-interest?id=417
The December 2014 issue of Fusion in Europe focuses on work underway—including novel types of simulations and materials research—to support the early design of DEMO, the machine that will come after ITER. The issue also covers the reorganization of fusion research in Europe under the banner of EUROfusion and brings news from some of the experiments planned in European fusion facilities in support of ITER.   You can read the latest Fusion in Europe here.

Collaboration with the Host Organization CEA

https://www.iter.org/of-interest?id=420
​Since the early days of project implementation in Saint-Paul-lez-Durance, France, ITER's closest neighbour and host—the French Alternative Energies and Atomic Energy Commission, CEA (Cadarache site)—has provided a number of services to the ITER Organization. These services are provided within the framework of the Site Support Agreement, which was signed in 2009 by the two entities as foreseen in the ITER Agreement and its Annex on Site Support. Regular meetings of the Site Liaison Committee, bringing together representatives from both organizations, are the occasion to discuss pending issues, exchange information and review actions underway.  On 10 December 2014, during the 10th Site Liaison Committee meeting, the ITER Organization and the CEA signed two agreements.   1. Agreement on organizational modalities in the event of emergency situations Agreement which defines the information, support and response modalities between the CEA/Cadarache and the ITER Organization in the event of any emergency liable to trigger, or not, emergency action plans. 2. Agreement related to the management of environmental aspects on the ITER site Agreement which defines the relations between the ITER Organization and Agence Iter France (the CEA agency created to manage the French contribution to the project) related to the environmental commitments undertaken by Agence Iter France, such as the definition of an environmental management plan for the 1,200 hectares on and around the ITER site. This agreement entered into force on 10 December 2014 and is concluded for the duration of implementation of the environmental management plan (31 December 2032). An aerial view of the CEA-Cadarache site.

Korea awards contract for vacuum vessel gravity supports

https://www.iter.org/of-interest?id=419
​The Korean Domestic Agency signed an important contract with Korean supplier Wonil Corp. for the ITER vacuum vessel gravity supports on 11 December 2014. Nine sets of gravity supports will be assembled under the lower ports to allow for the vacuum vessel's thermal expansion and to sustain loads in the radial, toroidal and vertical directions. The supplier Wonil Corp. is a leading company in the heavy machining industry and has good experience with the ITER quality system through its participation in the procurement of the ITER blanket shield blocks and the assembly tooling. During the signing ceremony, the company strongly expressed its enthusiasm to carry out the mission and meet the demands of the vacuum vessel schedule and quality requirements for ITER.   - Ji-Min Song, ITER Korea