They sailed on a warship. Some say that they wanted to show their military might; others that they felt too old—although they were both barely over 60—or too embarrassed to arrive for a state visit in an outdated two-engine Ilyushin propeller plane (1). Whatever the reason, the arrival in Portsmouth, UK, of a Soviet cruiser (escorted by two destroyers) carrying Nikolai Bulganin, President of the Council of Ministers of the USSR, and Nikita Khrushchev, Secretary of the Central Committee of the Communist Party, caused a sensation. The date was 18 April 1956 and this was the first-ever visit of Soviet leaders to the West.   The invitation had been extended by Prime Minister Anthony Eden at a Summit meeting held in Geneva the year before. Three years after Stalin's death, the time seemed ripe for an easing of tensions between the two "blocks" and for a shift toward "the peaceful coexistence between states with differing political and social systems," to use Khrushchev's words to the Twentieth Congress of the Communist Party in February 1956.   The April 1956 visit marked a first and decisive step in that direction: Soviet and British leaders were to discuss security in Europe and tensions in the Mideast, the expansion of trade and, hopefully, to "reach an agreement on cooperation in the peaceful use of nuclear energy."   The Soviets were confident. Having tested their first H bomb in 1952, they had reached strategic balance with the US—the sine qua non condition for "peaceful coexistence" with the West.   Accompanying Bulganin and Khrushchev to the UK was the man to whom the country owed this achievement.   "Of foremost significance among the more important problems of modern engineering science is utilization of the energy of thermonuclear reactions," read the first sentence of Igor Kurchatov's adress to Harwell researchers. "Physicists the world over are attracted by the extraordinarily interesting and very difficult task of controlling the thermonuclear reaction." Igor Kurchatov (1903-1960) had been running the Soviet nuclear program since 1943. Now that the USSR was on an equal strategic footing with the US, "The Beard," as he was known to his colleagues at the Laboratory of Measuring Apparatus of Academy of Science (in fact, the Institute for Atomic Research) could now focus his remarkable energy on another quest, maybe the most promising but also the most difficult of all: "the thermonuclear synthesis problem" —in other words, the harnessing of thermonuclear energy for peaceful uses.   And with the blessing of his political patrons "The Beard" was ready to share his results, doubts, and expectations with his colleagues from the West. It is hard to imagine, from a distance of 60 years, the impact and echo of Igor Kurchatov's conference at the Atomic Energy Research Establishment in Harwell, Oxfordshire — the Holy of Holies of Britain's nuclear research.   "In one bold stroke," writes Robin Herman in Fusion, The Search for Endless Energy (2), "the Soviet Union overturned the rules of the Cold War information game. Kurchatov laid bare the fact that for the past six years his nation had been conducting research in controlled fusion." Soberly titled "The possibility of producing thermonuclear reactions in a gaseous discharge," his address was a watershed moment in the young history of fusion research.   Not that it contained any revelation. The 300 Harwell physicists who attended the conference discovered that Soviet scientists "had been following very similar lines of research into magnetic confinement as the UK and the US," write Gary McCracken and Peter Stott in Fusion the Energy of the Universe.   Like their American and European counterparts, the Soviets had developed straight and toroidal pinch experiments, observed neutron emissions and short spurts of hard X-rays in deuterium plasmas, and acknowledged that quite a number of facts "remained to be explained."   Backed by equations, diagrams and high-speed photographs of plasma discharges, Kurchatov's speech did not contain an explicit call for international collaboration. But in shedding light on methodology and experimental results it challenged scientists in the West to reciprocate.   While scientists on both sides were eager to collaborate, many in Western government circles were reticent, especially in the US where it was felt that the Soviet opening was a ruse—a trick to lure politically naïve physicists into giving away precious state secrets.   While Kurchatov headed the "Institute" where fusion research was conducted, the investigative work was conducted by Lev Artsimovich (1909-1973) — a major role that Kurchatov acknowledged in the introduction to his Harwell speech. It took time to convince politicians that, at that stage, collaboration in the field of fusion was about fundamental science and didn't pose any threat of strategic or military nature. Only in September 1958, in Geneva where the United Nations held its Second International Conference on the Peaceful Uses of Atomic Energy, did the seeds that were sowed in Harwell begin to sprout.   There, for the first time and with the blessing of their governments, the main actors on both sides of the Great Divide—Artsimovitch , Teller, Spitzer, etc.—met face-to-face and exchanged notes. "They had a tremendous amount in common," writes Robin Herman, "an idealistic goal, a daunting intellectual problem and [...] a parallel history of frustration."   A "world fusion community" was born, determined to embrace what Kurchatov's speech had described as "the extraordinarily interesting and very difficult task of controlling thermonuclear reactions."   Sixty years after Harwell, the task — considerably longer and more difficult than anticipated — is nearing completion.   (1) The twin-jet Tupolev Tu-104 was still being flight-tested at the time of the visit. It was the world's second jetliner to enter commercial service in September 1956.   (2) Fusion, The Search for Endless Energy, by Robin Herman: Cambridge University Press, 1990.   Click here to view a video of the Soviet delegation's visit to Harwell on 26 April 1956.

With a crucial report from the US Secretary of Energy due shortly to the US Congress, an important US Congressional oversight body asked the ITER Director-General to visit Washington, D.C. for a public discussion on ITER's progress. The formal invitation came from The Committee on Science, Space, and Technology Subcommittee on Energy of the US House of Representatives—and specifically from the head of the subcommittee, Chairman Randy Weber (Republican-Texas). The focus of the meeting was "an overview of fusion energy science."   In addition to Director-General Bigot, two US fusion experts were asked to testify: Stewart Prager, Director of the Princeton Plasma Physics Laboratory; and Scott Hsu, a scientist from the physics division of Los Alamos National Laboratory.   The hearing was not only about the ITER Project. Other fusion projects, mostly US based, also figured into the questions. But it seemed no coincidence that the hearing occurred only five days after the completion of the ITER Council Review Group report: a probing dissection of the health of ITER reform efforts.   On another timely note: just one week from today, on Monday, 2 May, US Secretary of Energy Ernie J. Moniz is required by US law to deliver to the Congress his own assessment of ITER's progress, with a thumbs-up or thumbs-down on whether the US should remain an ITER Member.   That pending decision formed a dramatic backdrop to the subcommittee hearing. In many ways it was positive. Chairman Weber referred to Bigot's performance to date as "stellar and inspiring." He put a welcome spin on the international nature of the project: "We must consider the importance of access to the ITER reactor for American researchers and America's standing and credibility as a global scientific collaborator. If the US is going to lead the world in cutting edge science, we cannot take our commitments to our international partners lightly and we cannot undermine progress on complex projects."   Most of the members of Congress who spoke were similarly complimentary about ITER's recent progress. Representative Hultgren (Republican- Illinois) made one such remark: "... from all that I have heard, the ITER Project seems to be in a much better place than it has been in the past." For the ITER staff listening to the live stream, having experienced the rigours of the past year, it was "music to the ears" to hear this type of recognition from governmental leaders.   Not all questions had easy answers. Some committee members questioned the long-term nature of the ITER Project, seeking a shorter-term solution. Others asked detailed questions that exposed the confusing cost elements and complex organizational structure of the project.   In one interesting exchange, Representative Loudermilk (Republican-Georgia) asked Director-General Bigot whether, given the chance to start over, he would advocate the same multinational project structure. Dr. Bigot's answer showed a deft diplomatic touch: it would have been better, he said, if the elements of the recent Action Plan had been implemented at the beginning of the project.   Perhaps the best context was set by Stewart Prager, another witness, when he declared, without hesitation, that ITER will be "a landmark experiment in science and energy of the 21st century ... the focus of the world fusion energy program, complemented by strong domestic research in each participating nation."   For the link to the full hearing, see the Subcommittee website.   Click here for the full text of Director-General Bigot's written testimony to the Committee.   Click here for the full text of Director of the Princeton Plasma Physics Laboratory Stewart Prager's written testimony to the Committee.

A festive ceremony was held on 6 April at CEA Saclay's Cold Test Facility, near Paris, to mark the final acceptance, the cryogenic testing validation and the preparation of shipment to Japan of the first toroidal coil for JT-60SA. A few years before ITER is due to come into operation, the advanced superconducting "satellite" tokamak JT-60SA, conducted under the Broader Approach Agreement between Japan and Europe, will start operation. JT-60SA will model proposals for optimizing plasma operation and investigate advanced plasma modes that could be tested on ITER or used later on DEMO.   Assembly has been underway since 2013 in Naka, Japan.   The design activities for the JT-60SA toroidal field coils took place during 2007-2011 and were widely shared between European and Japanese institutions: Japan Atomic Energy Agency (JAEA), the European Domestic Agency for ITER, ENEA (Italy) and CEA (France).   Manufacturing activities were no less the fruit of international collaboration—the European agency for ITER procured the superconducting strands, which were manufactured by the Japanese firm Furukawa; the strands were cabled and jacketed by the Italian consortium ICAS; the coil cases were procured by ENEA and manufactured by Walter Tosto (Italy); and the coils were manufactured by Alstom/GE for CEA and ASG for ENEA.   Following cold testing at CEA's Saclay facility, the first toroidal field coil is now ready for shipment to Japan.   The ceremony on 6 April was held under the patronage of Ichiro Ikeda, Scientific Counsellor of the Japanese Embassy in Paris; Robert Aymar, who pioneered the development of superconducting tokamaks at CEA and led the ITER Project from 1993 to 2003; and Maria Faury, French Contact Person to the Broader Approach Steering Committee.   A CEA press release is available in French.

In early April, more than 50 experts met in Korea to discuss the fabrication of the ITER vacuum vessel, a technically challenging procurement that involves four ITER Domestic Agencies, the ITER Central Team and a large number of industrial contractors. In 2015, representatives from all involved parties were reunited in the Vacuum Vessel Project Team, created by the ITER Executive Project Board to promote synergies, the sharing of experience, and the rapid resolution of fabrication issues for the vacuum vessel sectors, ports and in-wall shielding.   The vacuum vessel is a double-walled, hermetically sealed stainless steel vessel that houses the fusion reaction and acts as a first safety containment barrier. In the space between the double walls, steel in-wall shielding blocks will provide protection from neutron radiation for components situated outside of the vessel; in addition, cooling water will circulate to remove the heat generated during operation. Openings, or ports, in the vacuum vessel will provide access for remote handling operations, diagnostics, heating, and vacuum systems.   At the Project Team meeting held from 4 to 7 April at the National Fusion Research Institute and Hyundai Heavy Industry, members of the ITER Organization, the Domestic Agencies of Europe, India, Korea and Russia, and contractors AMW (Ansaldo Nucleare S.p.A, Mangiarotti S.p.A and Walter Tosto S.p.A.), Avasarala Technologies Ltd, Hyundai Heavy Industry, MDT (MAN Diesel & Turbo SE) and ENSA discussed manufacturing challenges—including complex interfaces, instrumentation, tolerances and technologies—and opportunities for simplification and improvement.   Already, collaboration within the Project Team has led to a marked acceleration in document review and approval time, the establishment of a baseline schedule for all procuring Domestic Agencies for monitoring purposes, and the much-improved resolution of interface issues. All participants to the April meeting agreed to keep on in this spirit.   View photo gallery below.

Indian contractor Larsen & Toubro has completed the welding, non-destructive examination and trial assembly of this 30-metre transportation frame for the ITER cryostat. It will now be disassembled and shipped in sections to the ITER site.   Three steel frames like this will be necessary to support components, jigs and fixtures during the cryostat assembly process. The 30 x 30 metre assembly platforms will also act as transporters for the completed cryostat sections.   The first-completed section, the cryostat base, will be stored in the on-site Cryostat Workshop and later transported to the Assembly Hall cleaning facility and, beyond, to installation in the Tokamak Pit. The lower and upper cylinders will be stored on the platform on their frames until needed for in-pit assembly.   The fourth segment of the cryostat—the top lid—will most probably be assembled on the frame that had originally served the cryostat base.

A few hours before the last leg of the journey, on 21 April, the twin girders for the double overhead travelling crane are parked in the countryside, 20 kilometres to the east of the ITER site.   Soon, a small crowd will join — Head of convoy, drivers, mechanics, assistance and security personnel, French gendarmes... all in all, close to 150 people in two dozen vehicles.    At 10:00 p.m., the head of convoy will signal departure. By then, night will have fallen. Like a long steel serpent in a halo of blinking and pulsating lights, the convoy will slowly start moving.   Six hours later, one of the longest convoys that ever travelled the roads of southern France (some 250 metres from head to tail) arrived at the ITER site.   The four girders are now safely stored inside the Poloidal Field Coils Winding Facility. Their installation in the Assembly Hall is scheduled for June.

On April 6, 2016, the largest-scale nuclear industry exhibition in China opened its doors and the ITER Project was there. For four days, the actors of the global nuclear industry gathered in the National Convention Center in Beijing for the 14th China International Nuclear Industry Exhibition. One of the themes of the conference was "Fusion & Plasma Technology Applications." The Chinese Domestic Agency for ITER (ITER China) was invited to participate by one of the sponsors of the event, the Chinese Nuclear Society. At its 36 m² stand, complete with graphic display boards, model exhibits and promotional videos, the public was given a comprehensive introduction to the ITER Project, the status of domestic fusion research and development, and the specific contribution of China to ITER. The Director-General of the ITER Organization, Bernard Bigot, and the head of the Korean Domestic Agency, Kijung Jung, both visited the ITER stand, as well as representatives from institutes, universities, and suppliers involved with fusion at home and abroad.