The US is responsible for 14% of port-based diagnostic systems, including integration of 4 diagnostic port plugs, plus 7 instrumentation systems out of a total of approximately 40 individual diagnostic systems. The European Union, Japan, the Russian Federation, China, Korea, and India are also contributing to ITER diagnostics.
ITER diagnostic systems provide measurements to aid understanding of plasma behavior and optimize fusion performance. Because of the harsh environment inside the tokamak vacuum vessel, these systems must cope with a range of conditions not previously encountered by diagnostic technology, all while performing with high reliability. US diagnostics will include microwave, laser, x-ray, and optical systems. The US will provide design, fabrication, assembly, and testing of US port plugs, specifically the Upper Ports (U11, U17), Equatorial Ports (E3, E9), and Lower Port Structures (L8). In addition, the US will support the integration into these plugs of multiple diagnostics, including some from other domestic agencies.
The US will also be responsible for the following instrumentation systems: Upper IR/Visible Cameras, Low Field Side Reflectometer, Motional Stark Effect Polarimeter, Electron Cyclotron Emission Radiometer, Toroidal Interferometer/Polarimeter, Core Imaging X-ray Spectrometer, and Residual Gas Analyzer.
For more information, contact: Hutch Nielson, US ITER Project Office Diagnostics Team Leader (Acting), Princeton Plasma Physics Laboratory, hneilson@pppl.gov | 609-243-2726
The I&C team has completed a number of design achievements in preparation of First Plasma deliveries, including: Ion Cyclotron Heating (RF Bldg.) I&C First Plasma Final Design Review (December 2017), Tokamak Cooling Water System I&C First Plasma Final Design Review (November 2017), Vacuum Auxiliary System (03) Conceptual Design Review (July 2017) and Roughing Pumps System I&C Conceptual Design Review (April 2017).
Princeton Plasma Physics Laboratory and Oak Ridge National Laboratory, in collaboration with industry and universities, are developing the US contributions to ITER diagnostic systems. At this point, six of seven US diagnostic systems are in preliminary design with teams actively investigating physics and engineering issues through testing, prototype development and proof-of-principle activities.
As of October 29, 2014, procurement arrangements governing all 11 US ITER diagnostic systems have been signed with the ITER Organization; these arrangements define and assign the design, procurement and delivery responsibilities for the US.
When the ITER experimental fusion reactor begins operation in the 2020s, over 40 diagnostic tools will provide essential data to researchers seeking to understand plasma behavior and optimize fusion performance. A port plug integration proposal developed with the US ITER diagnostics team has helped the international ITER collaboration arrive at a clever solution for safely housing all of the tokamak diagnostic devices.
Understanding and monitoring electron density profile evolution and density fluctuations is essential for assessing the stability of fusion performance inside a tokamak. A new system that monitors electron density, known as the low field side reflectometer, is one of US ITER’s diagnostics contributions to the ITER tokamak now under construction in France.
