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ITER NEWSLINE 138
In the early afternoon of Tuesday, 28 June 2005, Akko Maas was sitting in his office on the CEA site in Cadarache closely following the news coming in from Moscow. Two hours prior, the decision had been made at a ministerial meeting that ITER would be built in Cadarache. That was good news indeed for Akko—a member of the core team in charge of the ITER site studies and the follow-up of all administrative matters.
Since late 2000 the team had been working hard to have ITER sited in Europe. In 2001, at the beginning of negotiations on the implementation of the ITER Project and its location, four sites had been proposed: Clarington, Canada; Rokkasho, Japan; Vandellós, Spain; and Cadarache, France.
Five years later, hard work and tough negotiation had finally paid off ... ITER was coming to Cadarache. Just as Akko was about to relax, the telephone on his desk rang. On the other end of the line was the Office the Director of the CEA Cadarache, Pascale Amenc-Antoni. Three words later, and all thoughts of relaxation had come to a sudden end for Akko. "Chirac is coming!" and "Elysée wants us to invite all the CEA staff."
3,000 people was a lot to deal with ... especially in a day and a half. President Chirac's arrival was announced for "the day after tomorrow." Only 36 hours for Akko and the rest of the site support team to organize a logistical miracle.
By the following morning, buses to transport the staff to the Cadarache Château were organized, tents had been put up, and the carpets rolled out ... not just any carpets, of course, but the official carpets that always accompany a French president, as well the official flags and the official speaker's desk. No one was allowed to walk over the carpet with shoes, and so Akko—the test person for the camera crews—was in stocking feet many times that day.
Extreme challenges require extreme measures ...
Air conditioning systems were installed "which indeed cooled down the room temperature," says Akko, "but they made so much noise than when the President started to speak they had to be turned off," leaving both the speaker and the audience defenseless against the heat.
At 7:00 p.m. the night before the event, it was decided to organize vapour fans for the audience waiting outdoors. "But our service company had none in stock!" says Akko. A company in Brussels had 25 fans available, and they were able to send them overnight. Also, 2,000 bottles of cooled champagne arrived right on time the next morning. "That was impressive, amazing," recalls Akko.
Despite the passage of time, many scenes from the day are still fresh in Akko's mind: the President's helicopter landing behind the Château; the traffic jams around the CEA centre and the access roads; the nervous looks on the faces of the security personal as the President dove into the crowds and shook as many hands as possible; and also the vacuum that remained behind as the booming sound of the chopper's rotors finally faded away. "That event was exceptional in many ways," Akko recalls. "It was both a nightmare and a dream."
Fusion plasmas are turbulent. They develop a large variety of instabilities and fluctuations that drain energy out of their core and reduce the overall performance of fusion devices.
The physics that drive turbulent phenomena are now well identified. Finding means to mitigate their consequences however, remains extremely difficult. Detailed measurements of turbulence are in high demand within the fusion community, as they hold the keys to predicting and controlling the quality of fusion plasma confinement in future tokamaks.
Fluctuations and dynamics in a fusion plasma can be probed by way of microwave radar beams, a technique referred to as "doppler reflectometry" that is routinely implemented in tokamaks around the world, among them DIII-D, Asdex Upgrade and, next door to ITER, Tore Supra.
At Tore Supra, collaboration between the Plasma Physics Laboratory (LPP) at the École Polytechnique in Paris and CEA-Cadarache's Institute for Magnetic Fusion Research (IRFM) has led to the development of a reflectometry system called DIFDOP (doppler diffusion) that has been operated extensively since 2003.
By "shooting" microwave beams from different angles, DIFDOP gives access to different sizes of turbulences. Tore Supra's long discharges provide several seconds of "stationary plasma"—a time long enough for operators to perform up to 200 measurements.
"Observing the density fluctuations within the plasma and the dynamics of turbulences at different scales helps us understand how energy is transferred between these different scales," says Laure Vermare, a physicist at École Polytechnique and a member of the LPP-IRFM collaboration. "This understanding will prove very useful in predicting what will happen in ITER."
DIFDOP has also yielded precious information about the rotating speed of the plasma, a yet little-understood phenomenon that has a stabilizing effect on plasma turbulence as well as on the repartition of the energy fluctuations over the different spatial scales.
Recently, EFDA issued a call for the development of new, powerful tools to study one specific behaviour of fusion plasma turbulence, possibly linked to an improvement of the plasma confinement. LPP and IRFM answered with a joint proposal to develop an additional diagnostic system, also based on doppler reflectometry and backscattering.
This vertical reflectometry diagnostic (DREVE) was installed at Tore Supra in March 2010. When the installation resumes operation in October, DREVE's data will be combined with that of DIFDOP to provide a much clearer picture of the movements inside Tore Supra's plasmas and, by extension, inside fusion plasmas in general.
Having one eye (DIFDOP) that looks into the equatorial plane of the plasma and another one (DREVE) that peers "from above" in the toroidal direction should provided physicists with a treasure trove of information.
"Recent observations on the TJ-II Tokamak, in Spain," says Laure Vermare, "suggest that a form of organization of the turbulence occurs in the transition to the H-Mode. How this transition takes place is still a bit of a mystery. What we are doing here, on a machine that does not operate in H-Mode, is testing new tools that will help us understand this crucial transition."
The H-mode, said its "discoverer" Fritz Wagner in an interview with Newsline last year, is what "makes the goals of fusion possible." Hence the importance of unveiling its secrets ...
The "Picture of the Week" in Newsline #132 featured a sign posted on the entrance door of one of the 525 buildings that recommended closing the doors in the evening to prevent wild boars from entering the premises.
As this picture illustrates, there was good reason. Bruno Couturier from Agence Iter France snapped this shot in July 2007. The young boar entering his office in building 521 was visibly undeterred by human presence.
That's what happens when men and beasts share the same enclosed territory for 50 years!
As a student of engineering in Montevideo, Uruguay in the 1970s, nothing predestined Cesar Luongo for a coveted position in Stanford University's graduate engineering programs. Nothing, that is, except ambition, confidence in his abilities and exceptional scores on the requisite entrance examinations.
"Uruguay was not on the map for US universities at that time at all ... we suffered from a total lack of visibility. I was the first student from Uruguay to ever be admitted to the Stanford Engineering School. Once there, of course, I didn't want to go down in history as the first and last Uruguayan student ... I felt like I had the weight of an entire country on my shoulders!"
With characteristic thoroughness, Cesar consigned to paper everything learned during his bid for admittance to Stanford in the hopes that it would serve other students ... and it did. Classed on the shelves of the University of Uruguay library, his 30-page, hand-written booklet filled with flow diagrams helped three generations of Uruguayan students find their way into graduate programs in the US.
"I keep in touch with those who followed in my footsteps," says Cesar. "I'm a bit of a mentor to them. They're scattered all over the world now—some as professors in Hong Kong, New York, or Strasbourg, others working for Hewlett-Packard or Exxon ..."
Cesar excelled at Stanford, studying magnetohydrodynamics and earning Master's and PhD degrees in mechanical engineering. Directly out of graduate school he joined the Bechtel Corporation in San Francisco where he remained a total of ten years, working on the analysis and design of large-scale superconducting magnets and becoming familiar with the team-based design processes used in industry.
He left Bechtel and the private sector in 1999 to become Professor of Mechanical Engineering, Associate Chair and Graduate Program Coordinator at Florida State University (FSU)—home to the National High Magnetic Field Laboratory. He received the Chair's Award for Excellence in Teaching in 2002 and the Dean's Award for Exceptional Research Productivity in 2007.
On the occasion of a one-year sabbatical from FSU, he joined the Magnet Division at ITER in 2008. "Coming to ITER, where the world's largest magnet system is being designed and built, was a once-in-a-lifetime opportunity for me. The ITER Tokamak is very complex and the challenges are enormous—any engineer would want to be a part of that," says Cesar.
One year turned into two ... and in June 2010, Cesar became a member of ITER staff.
As Senior Magnet Coordinator, Cesar plays a central role in the coordination of all the technical activities of the Magnet Division. He supports the Sections in the preparation of documentation for design reviews and Procurement Arrangements, and in the definition and tracking of the interfaces that exist between the ITER magnets systems, and between the magnets and other systems.
"There is a good part of negotiation inherent to my job," explains Cesar. "I'm the ambassador of the Magnet Division when it comes to interacting with other systems, and I believe my experience in private industry and as a university professor has been very relevant. I used to tell my students that engineering design is not only a technical but also a social activity ... ultimately, it's all about the issues of how to integrate a complex design in the context of a team effort, so there is always a very important human element involved."
Moving to France has been a second emigration for Cesar and although he speaks Spanish and English, he doesn't yet master French. "I come from a country which was built by immigrants so the mentality still is—you go where you think you can make a better life for yourself," says Cesar. He and his wife enjoy 'a simpler lifestyle' in Aix—no car, lots of walking—and their apartment under the eaves in a building formerly owned by the Cézanne family. Two grown children back in the United States are entering graduate programs this year, one in neurobiology and the other in mechanical engineering.
At ITER, Cesar enjoys working with colleagues encountered in the field of magnets and applied superconductivity over the years, and the fast-paced, dynamic environment ... "there's not much time to get bored!" As for the occasional pastime, Cesar is rumoured to be a fine connoisseur of jazz ...
In the March edition of Scientific American, Michael Moyer's article "Fusion's False Dawn" starts out: "Scientists have long dreamed of harnessing nuclear fusion—the power plant of the stars—for a safe, clean and virtually unlimited energy supply. Even as a historic milestone nears, skeptics question whether a working reactor will ever be possible."
Some members of the US fusion community speak out in a Letter to the Editor in this month's issue, taking issue with the fact that the article may leave the impression that informed scientists have become skeptical about fusion. "Fusion scientists consider their goal to be more tractable and relevant than ever before ..." they argue.
From 2-7 July, the ITER Organization will be exhibiting at the European Science Open Forum (ESOF) held in Torino, Italy. ESOF is a biennial European meeting dedicated to research and scientific innovation conceived by Euroscience, an organization that brings together scientists from 40 European countries.
Within the frame of the ESOF conference, the Euroscience Media Awards, Europe's leading prizes for journalists, television and public relations staff, will be awarded on Tuesday, 6 July. The judges selected the ITER Organization and its communication strategy "Distribution is all" as the winner of this year's AlphaGalileo Foundation Ltd. Public Relations award.
The ITER entry was described by one judge in these terms: "The emphasis at ITER is on the 'journey to science.' You get a strong and clear sense of being on it with them—a well thought through solution and a very strong entry." Another commented, "I liked very much the playful use of Facebook and the videos uploaded. This item seemed to reach out to a younger audience than usual."