title: Implementation of an in-vessel calibration light source for JET.
abstract: An in-vessel calibration light source (ICLS) has been implemented for remote use             during extended shutdown periods of the Joint European Torus (JET). The ICLS facilitated             the in situ calibration of optical diagnostics, which previously were performed when the             diagnostics were removed from JET. Since the ICLS is used to calibrate diagnostics over             the entire, exact optical path as used when plasma discharge data are measured, the ICLS             calibration implicitly accounts for any vignetting losses in the JET vessel viewports in             addition to the vacuum window transmission. At least ten diagnostic systems have             benefited from the ICLS during the extended ITER-like wall shutdown of 2009-2011.             Examples of the use of the ICLS in JET are given.
authors.affiliation: Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. tmbiewer@ornl.gov
authors.forename: T M
authors.initials: TM
authors.lastname: Biewer
authors.forename: C
authors.initials: C
authors.lastname: Belcher
authors.forename: I
authors.initials: I
authors.lastname: Hassall
authors.forename: D L
authors.initials: DL
authors.lastname: Hillis
authors.forename: G
authors.initials: G
authors.lastname: Kaveney
authors.forename: D
authors.initials: D
authors.lastname: Scharpf
authors.forename: M F
authors.initials: MF
authors.lastname: Stamp
authors.forename: C
authors.initials: C
authors.lastname: Stunell
authors.forename: K-D
authors.initials: KD
authors.lastname: Zastrow
mesh_terms: D002138:Calibration; D008027:Light; D060328:Magnetic Phenomena; D010825:Physics / Q000295:instrumentation*; D058626:Plasma Gases / Q000737:chemistry
chemical_list: D058626:Plasma Gases