I3.4 - Radiometric calibration of the NIRSpec instrument on the James Webb Space Telescope in the wavelength range from 0.7 μm to 5.0 μm

SENSOR+TEST Conferences 2009
2009-05-26 - 2009-05-28
Congress Center Nürnberg
Proceedings OPTO 2009 & IRS² 2009
IRS² 3 - Spectroscopy
R. Taubert, C. Monte, C. Baltruschat, B. Gutschwager, J. Hartmann, J. Hollandt - Physikalisch-Technische Bundesanstalt, Berlin, Germany, D. Kochems, C. Kuechel - EADS Astrium GmbH, München, Germany, M. Plate - ESA, Noordwijk, The Netherlands
249 - 254


The James Webb Space Telescope (JWST) with its 6-meter wide primary mirror is generally considered as the successor of the Hubble Space Telescope and the Spitzer Space Telescope. The JWST is an international collaboration between the NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA) and will be launched 2013.
The scientific instrumentation of the JWST consists of four instruments of which one is the near-IR multiobject dispersive spectrograph (NIRSpec), operating in the wavelength range from 0.7 μm to 5 μm. The NIRSpec instrument is foreseen to be calibrated on-ground at the Optical Ground Support Equipment by means of the Radiometric Calibration Spectral Source (RCSS) and in space by the NIRSpecs Internal Calibration Assembly. The RCSS is designed as a very low photon flux, point-like radiation source, typically with photon fluxes in the range from 10E4 to 10E7 photons·μmE-1·sE-1 in the wavelength range from 0.7 μm to 5 μm. It consists of a gold coated integrating sphere, several separately operable tungsten filament incandescent light sources with lead-glass bulbs, a 10 μm pinhole and a mirror-based optical imaging system. The RCSS is intended to be operated under vacuum and under cryogenic conditions.