RADCAM-A radiation camera system combining foil bolometers, AXUV diodes, and filtered soft x-ray diodes.

Measurements of radiated power are critical for characterizing and optimizing tokamak performance. The RADCAM system, comprising arrays of foil bolometers, Absolute eXtreme UltraViolet (AXUV), and filtered soft x-ray diodes, has been constructed to provide improved measurements of plasma radiation on "Tokamak a Configuration Variable" (TCV). An overview of the physical geometry, electronics, and design of the system is provided. The construction of the bolometer foils together with the improved sensitivity characteristics resulting from the inclusion of an anti-reflection carbon coating are presented. The large number of lines of sight in RADCAM are shown to significantly increase the spatial resolution over the legacy system. The system calibration procedure is detailed, and the mean system sensitivity is shown to vary by less than 5% over 1000 discharges. Additionally, the methodology for cross-calibration of the AXUV diodes with the bolometer foils is presented and applied to generate high temporal resolution measurements. The RADCAM radiation camera system is a compact, versatile system that is demonstrated to provide high resolution profiles of the radiated power in TCV.

[1]  G. Pautasso,et al.  Shattered pellet injection experiments at JET in support of the ITER disruption mitigation system design , 2021, Nuclear Fusion.

[2]  B. Duval,et al.  Initial TCV operation with a baffled divertor , 2021 .

[3]  Alexander Kramida,et al.  Development of NIST Atomic Databases and Online Tools , 2020, Atoms.

[4]  B. Duval,et al.  Disruption mitigation efficiency and scaling with thermal energy fraction on ASDEX Upgrade , 2020, Nuclear Fusion.

[5]  B. Duval,et al.  Progress toward divertor detachment on TCV within H-mode operating parameters , 2019, Plasma Physics and Controlled Fusion.

[6]  B. Duval,et al.  Experimental studies of the snowflake divertor in TCV , 2017 .

[7]  B. Duval,et al.  A novel carbon coating technique for foil bolometers. , 2016, The Review of scientific instruments.

[8]  A. Field,et al.  An FPGA-based bolometer for the MAST-U Super-X divertor. , 2016, The Review of scientific instruments.

[9]  Martine Baelmans,et al.  The new SOLPS-ITER code package , 2015 .

[10]  G. Zhuang,et al.  Upgrade of absolute extreme ultraviolet diagnostic on J-TEXT. , 2014, The Review of scientific instruments.

[11]  A. Burckhart,et al.  Application of AXUV diode detectors at ASDEX Upgrade. , 2014, The Review of scientific instruments.

[12]  P. Combette,et al.  Thermal stability of Pt/Cr and Pt/Cr2O3 thin-film layers on a SiNx/Si substrate for thermal sensor applications , 2013 .

[13]  Wonho Choe,et al.  Design and fabrication of a multi-purpose soft x-ray array diagnostic system for KSTAR. , 2012, The Review of scientific instruments.

[14]  W. Kasparek,et al.  Development and testing of 140 GHz absorber coatings for the water baffle of W7-X cryopumps , 2011 .

[15]  P. Detemple,et al.  Optimization of a bolometer detector for ITER based on Pt absorber on SiN membrane. , 2010, The Review of scientific instruments.

[16]  Xiang Gao,et al.  Diagnostics for first plasma study on EAST tokamak , 2008 .

[17]  I. Hutchinson,et al.  Two dimensional radiated power diagnostics on Alcator C-Mod. , 2006, The Review of scientific instruments.

[18]  M. Wischmeier,et al.  Radiation distributions in TCV , 2007 .

[19]  L. Giannone,et al.  Prototype of a radiation hard resistive bolometer for ITER , 2005 .

[20]  A. W. Degeling,et al.  AXUV bolometer and Lyman-α camera systems on the TCV tokamak , 2004 .

[21]  S. Luckhardt,et al.  Time resolved radiated power during tokamak disruptions and spectral averaging of AXUV photodiode response in DIII-D , 2004 .

[22]  K. Watanabe,et al.  Bolometer diagnostics for one- and two-dimensional measurements of radiated power on the Large Helical Device , 2003 .

[23]  Philippe Marmillod,et al.  Fast bolometric measurements on the TCV tokamak , 1999 .

[24]  J. Rice,et al.  High resolution bolometry on the Alcator C-Mod tokamak (invited) , 1999 .

[25]  P. J. Paris,et al.  X-ray tomography on the TCV tokamak , 1996 .

[26]  B. L. Henke,et al.  X-Ray Interactions: Photoabsorption, Scattering, Transmission, and Reflection at E = 50-30,000 eV, Z = 1-92 , 1993 .

[27]  C. Andelfinger,et al.  A Low Noise Highly Integrated Bolometer Array for Absolute Measurement of VUV and Soft X Radiation , 1991 .

[28]  J. F. Schivell,et al.  Performance of the Tokamak Fusion Test Reactor bolometers , 1985 .

[29]  C. Kunz,et al.  Optical constants from the far infrared to the x-ray region: Mg, Al, Cu, Ag, Au, Bi, C, and Al 2 O 3 , 1975 .