Upgrades to the in-vessel calibration light source on JET

Journal Article · Thu Aug 30 00:00:00 EDT 2018 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.5037713· OSTI ID:1467762

Conway, N. J.; Cackett, A. J.; Maggi, C. F.; Meigs, A. G.; Zastrow, K. -D.; Biewer, T. M. ; Hillis, D. L.

Since 2010, an in-vessel calibration light source (ICLS) has been used periodically on JET to calibrate a range of diagnostics at UV, visible, and IR wavelengths. During shutdowns, the ICLS (which is essentially an integrating sphere) is positioned within the vacuum vessel by the remote handling (RH) system. Following the 2013 calibration runs, several changes were made to improve the efficiency and quality of the calibrations. Among these was the replacement of a 20 m “umbilical” cable which carried power and other electrical signals through a vessel port to/from a control cubicle. A lightweight 2 m cable now plugs directly into a single connector on the RH manipulator system, greatly reducing the time required for deployment and improving operational flexibility; e.g., the vessel access “floor” no longer needs to be installed. This change also means the system would be compatible with calibrations after a high neutron-fluence period of operation. An on-board micro-spectrometer now allows for real-time verification of the emitted spectrum. Finally, new “baffles” were designed and installed within the integrating sphere itself, greatly improving the spectral radiance uniformity at non-normal viewing angles (necessary due to orientation uncertainties with the RH system).

• Sponsoring Organization: USDOE
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1467762
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Vol. 89 Journal Issue: 10; ISSN 0034-6748
• Publisher: American Institute of Physics
• Country of Publication: United States
• Language: English