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Discussing the implementation of ITER physics R&D: ITPA Coordinating Committee Chair Yutaka Kamada (front row, 2nd from left); IEA IA CTP Chair Steve Eckstrand (front row, 2nd from the right); ITER Director-General Motojima (front row, 3rd from left); David Campbell, Director of Plasma Operation Directorate (front row, 1st from the right) and colleagues.
Last week, a key meeting for the implementation of ITER physics R&D took place in the new Council Chamber. The Joint Meeting of the International Tokamak Physics Activity (ITPA) Coordinating Committee and the International Energy Agency Implementing Agreement (IEA IA) on Co-operation on Tokamak Programmes (CTP) is an annual gathering of senior representatives of the ITER Member fusion communities, the ITPA Topical Group leadership and program leaders from the major fusion facilities.

The 56 participants that had travelled from the ITER Members joined 12 from the ITER Organization for the meeting. In his opening remarks, ITER Director-General Osamu Motojima welcomed the participants, outlined the key priorities of the Unique ITER Team in relation to ITER construction, and underlined the major physics R&D needs. David Campbell, director of the Plasma Operation Directorate, gave an overview on the issues of physics R&D that are critical to the design and development of the ITER Research Plan.

Among these priorities are: the understanding and control of Edge Localized Modes (ELMs); disruptions and runaway electrons (and their mitigation); H-mode accessibility; use of all-metal plasma-facing components; the behaviour of tungsten impurities; tritium retention; dust; and power scrape-off layer (SOL) thickness.

The chairs of the seven ITPA Topical Groups reviewed the progress made in 2012 and proposed an experiment plan for 2013, focusing on the urgent issues for ITER. The Chair of Divertor and SOL Physics Topical Group, Emmanuelle Tsitrone, coordinated a special discussion session on the plan for joint research focusing on the comparison of divertors with carbon and tungsten plasma-facing components.

On the basis of high-priority research topics for ITER and the experimental capabilities of current fusion facilities, the facility program leaders decided on the priorities for each proposed experiment within their experimental programs for 2013. David Campbell commented, "I would like to thank ITPA for the continuing support of ITER R&D activities. We regard ITPA as a very important component of the ITER Project and a critical part of our physics R&D program, providing a great deal of input to the physics design basis for the completion of the ITER design—a high-priority activity at the moment."

On 13 December, Francesco Romanelli of EFDA-JET presented "JET results with the ITER-like wall."
On the afternoon last year when the team from the European tokamak JET attempted first plasma after an 18-month shutdown, Associate Leader Francesco Romanelli remained in his first-floor office. "I wasn't expecting the machine to perform so faultlessly on its first attempt," he later explained. "Besides, things had a way of going wrong when I entered the room, so maybe it was better after all."

That anecdote and others were related by Romanelli at last week's Inside ITER seminar, during which he gave a first-hand overview of the ITER-like wall campaign that has been running at JET since that first (very successful) day back in August 2011. Three thousand installable items and 16,000 tiles had been replaced in the machine (non-metal carbon tiles were replaced by the metals beryllium and tungsten) to equip JET with the same materials mix chosen for ITER.

Romanelli reported in detail on the experimental results so far: demonstration of low fuel retention, tungsten divertor successfully tested, observations related to the dynamics of disruptions ...

"Overall, the operation of the ITER-like wall has been easier than expected, giving us the confidence that the fusion community is making the right choice for ITER. We see JET as the main risk mitigation measure in support of ITER."

The European Fusion Development Agreement is already looking ahead to other roles for JET—developing plasma scenarios in ITER-relevant configurations and testing the compatibility of the wall with the use of tritium. "JET can provide unique input in a number of technical and operational areas."

David Campbell, director of ITER's Plasma Operation Directorate, agrees: "The crucial ITER-like wall experiment will give us insight—ahead of ITER operation—as to how fusion plasmas will behave in the presence of the plasma-facing mixture that we're planning to use in ITER."

For more on JET's ITER-like wall campaign, visit the EFDA-JET website.

Evolution of the plasma in PPPL's National Spherical Torus Experiment during a disruption, as captured by a fast color camera. The plasma is centred in the left-hand frame, moves downward in the centre frame, and lands on the floor of the vacuum chamber in the right frame. Large "halo currents" are observed in the indicated ring of detectors at this time.
The latest advances in plasma physics were the focus of more than 1,000 scientists from around the world who gathered in Providence, RI (USA) from 29 October-2 November for the 54th Annual Meeting of the American Physical Society's Division of Plasma Physics (APS-DPP). Papers, posters and presentations ranged from fusion plasma discoveries applicable to ITER, to research on 3D magnetic fields and antimatter. In all, more than 1,800 papers were discussed during the week-long event.

Researchers from the US Department of Energy's Princeton Plasma Physics Laboratory (PPPL) reported on experiments and computer simulations related to tokamak confinement and a variety of other research interests. These included specialized areas such as laboratory and astrophysical plasmas, where PPPL physicist Hantao Ji was prominent as a topic chair and speaker at a tutorial session.

Members of the Laboratory's National Spherical Torus Experiment Upgrade (NSTX-U) team gave a tutorial and three invited talks. Physicist Dennis Mueller presented the tutorial on "Physics of Tokamak Plasma Start-up."

The Laboratory sent 135 physicists, science educators and graduate students to the meeting and saw some of its research highlighted in news releases on the APS-DPP website. Of the 14 papers highlighted in this manner, seven came from PPPL.

The meeting focused considerable attention on boundary physics and plasma-material wall interactions, an area of growing emphasis at PPPL. Dennis Whyte, a professor of nuclear science and engineering at the Massachusetts Institute of Technology, presented a major review of the subject to a plenary session.

Invited speakers on the topic of plasma-wall and impurity physics included PPPL scientists Filippo Scotti and Dick Majeski, principal investigator for the Laboratory's Lithium Tokamak Experiment (LTX). PPPL physicists Michael Jaworski and Igor Kaganovich participated in a session on plasma-wall interactions, with Jaworski serving as chair and Kaganovich giving the first invited talk in the session.

The importance of boundary physics has been recognized in innovations like the so-called snowflake divertor, which limits the heat on tokamaks' inner walls. The divertor, developed by researchers at PPPL and the DOE's Lawrence Livermore and Oak Ridge national laboratories, won an R&D 100 Award in June from R&D Magazine. The device "reduces both the power flux on plasma-facing components and the influx of impurities into the core plasma," said PPPL physicist Robert Kaita, the head of diagnostics and physics operations for the National Spherical Torus Experiment Upgrade (NSTX-U), and co-principal investigator for the LTX.

Considerable interest also was shown for inertial confinement fusion experiments at the National Ignition Facility (NIF) at the DOE's Lawrence Livermore National Laboratory. Speakers noted that producing fusion by heating a capsule producing energy with high-powered lasers was proving more difficult than expected. NIF scientists now seek to develop a more detailed understanding of the physics of this process in order to achieve ignition.

Follow this link to APS press releases.

The panel that reviewed the low-voltage components was chaired by Michel Huguet, former head of the ITER Joint Work Site at Naka (Japan).
Coil instrumentation in ITER consists of some 3,000 sensors whose function is to monitor the essential parameters of magnets during ITER operation.

A EUR 25 million package, coil instrumentation forms one the few direct purchases of the ITER Organization and the only fund procurement of the Magnet Division. The components will be delivered by the ITER Organization to the Domestic Agencies involved in coil procurement.

Cryogenic and mechanical instrumentation components ("low-voltage" components) account for about one-third of the package's value. Measuring temperature, displacement, strain and deformation, the low-voltage sensors are critical. The Head of the Magnet Division, Neil Mitchell, explains: "These components cannot be maintained once they are installed. If one fails, it is lost. Of course there are redundancies, but we have to do our best to guarantee they will operate for 30 years in the harsh cryostat environment."

On 13-14 December, all of the low-voltage components were reviewed by a panel that included members of the different ITER departments and directorates, specialists from the Domestic Agencies, and also internationally reputed external experts.

This was the third Manufacturing Readiness Review organized by the ITER Magnets Division over the last two months. The first one was conducted on the safety class quench detection system on 23 October; the second on 29-30 November for investment protection quench detection and related high voltage components.

All three reviews were capably organised and run by Felix Rodriguez-Mateos, the Technical Responsible Officer for the magnet instrumentation, and his colleagues in the team.

Last week's low-voltage review panel was chaired by Michel Huguet, a major figure in the history of the ITER Project who joined fusion research in 1969 at CEA, spent 19 years at JET, and eventually headed the ITER Joint Work Site at Naka (Japan).

"The panel members were quite satisfied—I could even say impressed—by the quality of the work accomplished. Processes and strategies appear to be heading in the right direction."

Now that the results of the qualification tests have been reviewed (ITER uses laboratories located at CERN) the next step is to release the contracts for low-voltage components, which should be accomplished in the first half of 2013.

The PRIMA neutral beam test facility will host the prototypes of the ITER neutral beam injector, which will be tested and developed there.
Progress on the neutral beam test facility, PRIMA, was reported this week by the European Domestic Agency F4E. Hosted by Consorzio-RFX in Padua, Italy, this facility under construction will test ITER's large and powerful neutral beams in advance of operation.

The PRIMA neutral beam test facility will host the prototypes of the ITER neutral beam injector, which will be tested and developed there. The facility will host two independent test beds: SPIDER (Source for Production of Ion of Deuterium Extracted from Radio Frequency plasma), where the first full-scale ITER ion source will be tested and developed with an acceleration voltage up to 100 kV; and MITICA (Megavolt ITER Injector & Concept Advancement), which will be the first 1:1 full ITER injector aiming at operating up to the full acceleration voltage of 1 MV and a full power (16.5 MW).

Three procurement contracts were awarded during the last months for the manufacturing of PRIMA components. The contract for the SPIDER beam source and vacuum vessel, worth approximately EUR 7.5 million, was awarded to a European consortium formed by Thales (France), Galvano-T (Germany) and CECOM and Zanon (Italy). The contract for the cooling plant system, which will evacuate 70 MW of heat from the SPIDER and MITICA test beds, was awarded to the Italian company, Delta-ti Impianti S.p.A (EUR 8 million).

And finally, a EUR 2.5 million contract was signed for the vacuum and gas injection plant with Angelantoni Test Technologies (Italy), covering the design and construction of the gas injector that will provide the deuterium and hydrogen gas and the vacuum system that will pump (and deter) the gas from spreading.

Procurement of the main industrial contracts for SPIDER will be concluded with the award of the contract for SPIDER's high voltage deck and transmission line, currently in its final stages. From 2013 onwards, the remaining European contracts for MITICA will be awarded.

On site in Padua, the construction of the buildings for MITICA and SPIDER is progressing. This construction is funded by Italy, as part of its commitments as PRIMA host.

Read the full report here.

Adaptation and infrastructure works on the ITER site, November 2012.
The ITER site is set to go through one of its biggest transformations, following the signature by the European Domestic Agency F4E of a contract for site infrastructure works with COMSA EMTE.

Under this contract, for a value of EUR 35 million, a variety of civil engineering works such as lighting, drainage, special foundations, roads and trenches will be carried out. Eighty people will be deployed on the ITER site in order to ensure the coordination of the activities and reconfigure the 500,000 m² that will be directly affected by the works.

The civil engineering works carried out through this contract will deliver to the ITER site a fully integrated drainage system (process discharges, precipitation drainage and sanitary drainage), outdoor and indoor lighting, a water management system, service trenches for networks between buildings, roads and parking areas, and special foundations to support equipment and site installations.

A components cooling water network will be built to transfer heat from the systems for heat removal, operating side by side with the heat rejection system that will buffer heat loads during operation through an open loop system consisting of cooling towers, cold and hot basins, water pumps, valves, sensors and interconnected piping.

Read the full story on the F4E website here.