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In the course of °ÄÃÅÁùºÏ²Ê¸ßÊÖ operation, part of the tritium injected into the machine will not be "burned" in the fusion reaction. The leftover tritium will be pumped out (along with helium ash), separated and recycled to be reinjected into the plasma.   In the basement of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Tritium Plant, four storage tanks and two emergency tanks (for "off-normal" events) will handle the water involved in the recycling process. The emergency tanks, 100 cubic metres each, have now been delivered to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ site.   Procured by the European Domestic Agency and manufactured in Spain, the first tank arrived on 20 March and the second on 2 April. The four storage tanks (4 tonness each, 20 cubic metres) are expected in the coming months.

The 13th edition of the Conductor Meeting took place in Grindelwald, Switzerland from 17-19 March 2015 with the support of the plasma and fusion laboratory CRPP (Centre de recherches en physique des plasmas, Lausanne.)  Since March 2009, this meeting has been organized on a twice yearly basis to bring together the six Domestic Agencies involved in the procurement of °ÄÃÅÁùºÏ²Ê¸ßÊÖ conductors and their suppliers. In recent years, it has been extended to include the actors (Domestic Agencies and suppliers) involved with coil manufacturing to anticipate and/or cope with issues that arise on conductor delivery or acceptance. The most recent gathering in Switzerland was coupled with a meeting of the SULTAN working group, a long-running expert group in charge of reviewing the results and assessing the performances of full-size conductor sample tests and joint sample tests that are performed at the SULTAN facility in Villigen, Switzerland. The meeting was a good opportunity to herald the progress in conductor production. Nearly all niobium-tin (Nb3Sn) superconducting strands for the °ÄÃÅÁùºÏ²Ê¸ßÊÖ toroidal field coils have been produced by China, Europe, Japan, Korea, Russia, and the US—about 500 tonnes in all. Seventy percent of the toroidal field conductor unit lengths have now been completed (see chart). The meeting was a good opportunity to herald the progress in conductor production. Russia has completed the niobium-titanium (Nb-Ti) superconducting strands for °ÄÃÅÁùºÏ²Ê¸ßÊÖ's smallest poloidal field coils, PF1 and PF6, and Europe has begun manufacturing the conductor unit lengths. Two-thirds of the strands needed for poloidal field coils PF2-5 have been manufactured in China, as well as all unit lengths for coil PF5. Japanese and Korean suppliers have manufactured approximately 28 percent of the Nb3Sn superconducting strands required for the central solenoid coils and Japan has completed unit lengths corresponding to one (of six) central solenoid modules. For the °ÄÃÅÁùºÏ²Ê¸ßÊÖ correction coils and busbar conductors, China has produced the full amount (22 tonnes) of Nb-Ti strand; over half of the unit lengths for the correction coil conductor; both unit lengths for the correction coil busbar conductor; and two (of three) main busbar conductor unit lengths. Progress was also reported during the meeting on coil manufacturing. Europe has wound 23 toroidal field double pancakes while, in Japan, seven double pancakes have been manufactured by one supplier and a second is completing the manufacture of a dummy. Winding qualification activities for the central solenoid modules have been completed in the US and production winding is set to start in the coming weeks; Russia is currently carrying out winding qualification activities for the PF1 coil; and China has completed the fabrication and testing of a pair of high temperature superconductors for the correction coils. The SULTAN Working Group confirmed the good results of all full-size conductor samples tested as part of the comprehensive quality control plan for °ÄÃÅÁùºÏ²Ê¸ßÊÖ conductors. An amendment to the SULTAN contract signed in 2012—currently under preparation—would enable the Domestic Agencies that are still in production a priority use of the facility. The conductor meetings have been instrumental over the years in building up a project team spirit and mutual trust at the technical level.  The next meeting is planned for 21 September 2015 at °ÄÃÅÁùºÏ²Ê¸ßÊÖ Headquarters.

For a few days last week, the Mistral (the "master wind" of Provence) blew with sufficient force to "tear the horns off the oxen," as the local saying goes. On the °ÄÃÅÁùºÏ²Ê¸ßÊÖ site, we know of no oxen that suffered any loss, but a strong gust carried away the large flag that stood at the north edge of the platform.   On the more positive site, the Mistral does a fantastic job of cleaning the landscape, washing away the haze and bringing out the pristine colours of the land (and the construction site).

​After two years of intense maintenance and consolidation, and several months of preparation for restart, the Large Hadron Collider (LHC), the most powerful particle accelerator in the world, is back in operation. On 5 April at 10:41 a.m., a proton beam was back in the 27-kilometre ring, followed at 12:27 p.m. by a second beam rotating in the opposite direction. These beams circulated at their injection energy of 450 GeV. Over the coming days, operators will check all systems before increasing energy of the beams. "Operating accelerators for the benefit of the physics community is what CERN's here for," said CERN Director-General Rolf Heuer. "Today, CERN's heart beats once more to the rhythm of the LHC."   "The return of beams to the LHC rewards a lot of intense, hard work from many teams of people," said the head of CERN's Beam Department, Paul Collier. "It's very satisfying for our operators to be back in the driver's seat, with what's effectively a new accelerator to bring on-stream, carefully, step by step." The technical stop of the LHC was a Herculean task. Some 10,000 electrical interconnections between the magnets were consolidated. Magnet protection systems were added, while cryogenic, vacuum and electronics were improved and strengthened. Furthermore, the beams will be set up in such a way that they will produce more collisions by bunching protons closer together, with the time separating bunches being reduced from 50 nanoseconds to 25 nanoseconds. Read more on the CERN website.

By Raphael Rosen, Princeton Plasma Physics Laboratory NASA's Magnetospheric Multiscale mission (MMS), a set of four spacecraft that will study the magnetic fields surrounding Earth, may employ data provided by Princeton Plasma Physics Laboratory (PPPL), which operates the Magnetic Reconnection Experiment (MRX)—the world's leading laboratory facility for studying reconnection. Results of the MRX research could elucidate the space probes' findings, said Masaaki Yamada, principal investigator of the MRX project. Reconnection takes place when the magnetic field lines in plasma merge and snap apart with violent force. But NASA is flying blind in a sense when seeking such events, since mission operators don't know precisely where reconnection will occur in space or what the data it produces will look like. And since the explosive events occur in milliseconds, the MMS craft, orbiting in tight formation at an average speed of some 20,000 miles per hour, will have only fleeting moments to detect and measure the phenomena. The MRX data could facilitate such detection. Comparing the data with signals from space will enable instruments aboard the craft to spot actual instances of reconnection taking place. Read more on the PPPL website.

​When °ÄÃÅÁùºÏ²Ê¸ßÊÖ scientists needed to simulate how particles travel and transport radiation in the °ÄÃÅÁùºÏ²Ê¸ßÊÖ machine, they bought time in one of the most powerful supercomputers in Europe: Mare Nostrum, the flagship machine of the Barcelona Supercomputing Centre (BSC). The collaboration with the Spanish public institution, whose 10th anniversary was celebrated on 1 April, has now shifted to simulation studies of ELM control techniques — another field of study that requires crunching huge quantities of numbers. High performance computing has become essential to the progress of science and technology. With close to 50,000 processors and a computing power of one thousand billion operations per second, Mare Nostrum has contributed to establishing three-dimensional maps of the galaxy, mathematical models of the expansion rate of the Universe, the sequencing of the human genome... In a video address to the participants of the 10th anniversary ceremony, °ÄÃÅÁùºÏ²Ê¸ßÊÖ Director-General Bernard Bigot stressed the importance of BSC's contribution to °ÄÃÅÁùºÏ²Ê¸ßÊÖ. °ÄÃÅÁùºÏ²Ê¸ßÊÖ and the Spanish institution have crossed ways many times: former °ÄÃÅÁùºÏ²Ê¸ßÊÖ Deputy-Director Carlos Alejaldre was part of BSC's executive board in the mid-2000s and, more recently, one of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Monaco Postdoctoral Fellows joined BSC's computational physics group, bringing with him the valuable experience he gained while at °ÄÃÅÁùºÏ²Ê¸ßÊÖ.

Collaboration in European fusion research has a long history. In 1961, the Max Plank Institute of Plasma Physics became an associate of the European Fusion Programme, which comprised the fusion laboratories of the European Union and Switzerland. In the 1970s, the European fusion laboratories decided to build and operate the Joint European Torus (JET). In 2014, the program was restructured and EUROfusion formed as a consortium of 29 national fusion laboratories (Research Units). A goal of this reorganization is to efficiently implement a roadmap to the realization of fusion energy. The roadmap has been developed within a goal-oriented approach articulated in eight different missions (#8 focuses on the stellarator). It also prioritizes the financing of the fusion program.   In mission 8, the stellarator is being developed as an alternative concept for fusion electricity. The program concentrates on optimized stellarators based on the HELIAS principle—a stellarator line which was invented and developed at IPP. Wendelstein 7-X is a cornerstone of this line which is decisive for mission 8 and which will give answers to fundamental questions in plasma physics.     Read more in the Wendelstein 7-X March newsletter.