title: In situ wavelength calibration of the edge CXS spectrometers on JET.
abstract: A method for obtaining an accurate wavelength calibration over the entire focal plane of the JET edge CXS spectrometers is presented that uses a combination of the fringe pattern created with a Fabry-Pérot etalon and a neon lamp for cross calibration. The accuracy achieved is 0.03 Å, which is the same range of uncertainty as when neglecting population effects on the rest wavelength of the CX line. For the edge CXS diagnostic, this corresponds to a flow velocity of 4.5 km/s in the toroidal direction or 1.9 km/s in the poloidal direction.
authors.affiliation: Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169, USA.
authors.forename: E
authors.initials: E
authors.lastname: Delabie
authors.affiliation: CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB, United Kingdom.
authors.forename: N
authors.initials: N
authors.lastname: Hawkes
authors.affiliation: Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169, USA.
authors.forename: T M
authors.initials: TM
authors.lastname: Biewer
authors.affiliation: Department of Physics, University of Strathclyde, Glasgow G4 0NG, United Kingdom.
authors.forename: M G
authors.initials: MG
authors.lastname: O'Mullane
authors.affiliation: EUROfusion Consortium, JET, Culham Science Centre, Abingdon OX14 3DB, United KingdomOak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169, USACCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB, United KingdomDepartment of Physics, University of Strathclyde, Glasgow G4 0NG, United Kingdom.