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One last time the band got together again. Like old friends they didn't need words to salute each other—a slap on the shoulder at the coffee table, a respectful nod when entering the door was sufficient. They had come a long way but the job is nearly done and it was time to say goodbye.    Last week, from 15 to 17 September, representatives from the applied superconductivity community, members of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization and Domestic Agency magnet teams, and suppliers—the "band" as Superconductor Section Leader Arnaud Devred calls them—convened for one last time to celebrate the wind-down phase of an eight-year campaign to procure °ÄÃÅÁùºÏ²Ê¸ßÊÖ's superconductors.   Since 2008 the group has met twice yearly to facilitate the exchange of information, share experience, and identify synergies; now, with the manufacturing of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ superconductors drawing to a close, it was time to look back and celebrate.   For a special event held on the second day of the meeting, some of the grands seigneurs of the superconducting world were present in the amphitheatre of °ÄÃÅÁùºÏ²Ê¸ßÊÖ Headquarters. One of them was Bruce Strauss, program manager at the Office of High Energy Physics (US Department of Energy) and an eye-witness to the fast development of superconductors and their applications over the last decades.   Applauding the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization for its conductor procurement strategy, which has been instrumental in establishing processes and systems to standardize conductor production and testing around the world, Strauss said: "You have set the bar for managing a multi-vendor, in-kind acquisition strategy. My warm congratulations on the demonstrated success of this venture."   Valued at more than EUR 600 million, the 11 conductor Procurement Arrangements signed by the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization between 2007 and 2010—covering the procurement of conductors for the large toroidal field, poloidal field and central solenoid magnets as well as correction coils and feeders—represent one of the project's largest in-kind procurement packages. Six out of the seven °ÄÃÅÁùºÏ²Ê¸ßÊÖ Members (China, Europe, Japan, Korea, Russia and the United States) have taken part.   The °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization, in close collaboration with CERN, pioneered reporting, document handling and quality assurance procedures to ensure that strands produced by suppliers all over the world achieved the same required performances. More than 12,000 control points, relying on over 30,000 strand critical measurements, have been cleared in a timely fashion through a web-based database developed by the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Central Team, enabling production to run smoothly at approximately 20 suppliers around the world. Today, 70 percent of the manufactured conductor unit lengths have been accepted by the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization.   °ÄÃÅÁùºÏ²Ê¸ßÊÖ Director-General Bernard Bigot unveils a plaque that lists all of the contributing partners to °ÄÃÅÁùºÏ²Ê¸ßÊÖ's longest-lead procurement package. °ÄÃÅÁùºÏ²Ê¸ßÊÖ superconductors are manufactured from one of two types of advanced materials that become superconducting when cooled with supercritical helium in the range of 4 Kelvin (-269 °C)—niobium-tin (Nb3Sn) for °ÄÃÅÁùºÏ²Ê¸ßÊÖ's highest magnetic field applications or niobium-titanium (Nb-Ti).   "Project pull is decisive for applications," David Larbalestier, from Florida State University, reminded the audience, "and conductor development follows." For this world-known expert in the field, the fact that °ÄÃÅÁùºÏ²Ê¸ßÊÖ conductor procurement is drawing to a successful close heralds the beginning of a superconducting era.   Lucio Rossi, who was in charge of superconductors for CERN's Large Hadron Collider (LHC) and who is now project leader for the High Luminosity Upgrade, agrees: "Superconductivity has been an enabling technology for accelerators. For the LHC, niobium-titanium conductors were chosen due to cost constraints and the immaturity of niobium-tin in those days. But the search for 'better' never ends in science and niobium-tin will be the first choice material for the LHC Upgrade. With these high performance materials there is a 'super world' ahead of us."   "The impossibilities of the years 2005-2008 have become standard industrial technology in 2015," stressed the head of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Magnet Division, Neil Mitchell, during his talk on the "making-of" °ÄÃÅÁùºÏ²Ê¸ßÊÖ superconductors.   "It has been a long and winding road," said Arnaud Devred at the close of the fourteenth and last Conductor Meeting. "Our band will soon break up but, today, let's remember that together we have overcome many technical challenges. This has been an amazing human adventure."   Celebration chairman Robert Aymar—former director of both CERN and the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project—concluded in a final email to participants. "The final meeting on °ÄÃÅÁùºÏ²Ê¸ßÊÖ conductor procurement has given us all the opportunity to understand the status of production and conductor performances. We are now reassured that the conductors will be available on time to satisfy the needs of the coil manufacturers and that the conductors have margins in their performance to allow the magnets to satisfy their requirements. These are two very important results—bravo!!" A press release on the success of °ÄÃÅÁùºÏ²Ê¸ßÊÖ conductor procurement is available in English or French.

Plasma turbulence has been the bane of fusion scientists for decades. But now they're getting their own back—images of plasma inside the MAST tokamak at Culham are showing how turbulence could actually tackle one of the hottest issues in fusion reactor design.   Plasma is a fascinating but frustrating fact of life for researchers developing fusion energy. The fourth state of matter, despite making up most of the universe, still holds many secrets for Earth-bound physicists. Controlling this incredibly hot ionised gas in a magnetic field within a tokamak is a proven way of triggering fusion reactions, but the downside is that the plasma becomes turbulent and unstable, making it difficult to confine—analogous to the creation of blobs in a lava lamp, or the break-up of clouds in the sky.   The MAST videos provide the closest view yet of plasma in the tokamak's exhaust system, the divertor, and may hold the key to dealing with the intense heat ejected from the fusion chamber onto surrounding surfaces. This is a major concern for researchers designing full-scale tokamak power plants.   The divertor, made from extremely tough materials, acts as a target for the waste plasma, and pumps helium ash and impurities out of the tokamak. But in a fusion power plant the divertor will be exposed to power loads of tens of megawatts per square metre (many times greater than a spacecraft re-entering the atmosphere), putting a strain on even the toughest of structures.   Continue reading on the CCFE website. 

With winding of the first production module for °ÄÃÅÁùºÏ²Ê¸ßÊÖ's central solenoid well underway, the US Domestic Agency (US °ÄÃÅÁùºÏ²Ê¸ßÊÖ) and its contractor, General Atomics, are now commissioning all of the necessary tooling stations for the 13 Tesla, 1,000-metric-ton electromagnet. Eleven unique stations will form the module manufacturing line at the GA Magnet Technologies Center in Poway, California. One challenge to commissioning the unique stations is coming up with an appropriate coil that does not use any production conductor. The commissioning process requires a variety of trials to assure that the tooling will perform specific fabrication tasks as predicted. After commissioning, the workstation undergoes a manufacturing readiness review. "General Atomics has been very clever," said US °ÄÃÅÁùºÏ²Ê¸ßÊÖ central solenoid systems manager David Everitt. "They made what we call a 'Frankenstein coil' to test and commission numerous stations. This commissioning coil is made out of qualification samples of real conductor which were coupled with other samples such as empty jacket material." The commissioning coil is two layers high with real conductor on a portion of one layer of the coil. At the turn insulation station, fiberglass insulation tape will be wrapped around the wound conductor coils. Photo: GA "When you see everything that happens at General Atomics every day, you appreciate that they have a very talented crew out there. We have an innovative team who is highly invested in the project," said Everitt. So far, the coil has been used for commissioning activities at stations for joint and terminals preparation, stacking, joining plus helium penetrations, reaction heat treatment and part of turn insulation. All or part of ten of eleven stations are now in place at General Atomics and eight of these stations have completed some or all acceptance testing and commissioning activities. One of the more complex stations to install and commission handles turn insulation. This workstation wraps insulating fiberglass tape and Kapton around the conductor after the coils have been wound and heat treated. In order to wrap the conductor, the coil must be "un-sprung" for insulation wrapping and then reassembled. After insulation is completed, the coils move down the production line to the vacuum pressure impregnation station, where a three-part epoxy mixture is injected under vacuum to impregnate the previously applied turn and ground insulation materials that surround the coil. The epoxy provides both electrical insulation and structural support to the 110-metric-ton magnet module. A major investment has been the construction of a cold testing facility for the final testing of each module at 4 Kelvin, comparable to °ÄÃÅÁùºÏ²Ê¸ßÊÖ's operating temperature for the central solenoid. Commissioning of the cold testing facility is planned for early 2016, and equipment installation has begun. As the home of the DIII-D National Fusion Facility, General Atomics has a half-century long history with fusion. The Magnet Technologies Center has not only a 4 Kelvin cryogenic system needed for superconducting magnets, but also a large vacuum cryostat for testing magnets, a 50 kA, 10 V power supply, and a fast discharge dump circuit for magnet protection. See the original article here.

Last week's lift of the Assembly Building roof structure was a delicate operation that required close-to-perfect alignment between the vertical columns and the connexion plates on the roof structure. And close-to-perfect it was. Despite the relative flexibility of the steel structure, real-time metrological measurements showed that only 4 (out of 66) connexions ended up slightly misaligned. As a consequence, 4 new plates (1 m x 20 cm) will be machined to compensate for the slight misalignment. Working at a height of nearly 60 metres, workers are now placing and tightening 3,000 connexion bolts (out of 85,000 for the whole steel structure). This operation, along with the removal of the temporary structures that held the hydraulic jacks and cables, will take about two weeks to complete.

By Steven Cowley Chief Executive Officer of the UKAEA Head of the EURATOM/CCFE Fusion Association ​ This December, world leaders will gather in Paris for the United Nations Climate Change Conference, where they will attempt — yet again — to hammer out a global agreement to reduce greenhouse-gas emissions. Despite the inevitable sense of déjà vu that will arise as negotiators struggle to reach a compromise, they must not give up. Whatever the political or economic considerations, the fact remains: if global temperatures rise more than 2ËšC from pre-industrial levels, the consequences for the planet will be catastrophic. But the challenge does not end with reducing emissions. Indeed, even if we make the transition to a cleaner world by 2050, we will need to determine how to meet a booming global population's insatiable appetite for energy in the longer term — an imperative that renewables alone cannot meet. That is why we need to invest now in other technologies that can complement renewables, and provide reliable electricity for many centuries to come. And one of the most promising options is nuclear fusion — the process that powers the sun and all stars. (Photo Elle Starkman/PPPL) Read the full article on the WorldFinance website.