NIRSpec Ground Calibration
Guido De Marchi
ESA/ESTEC
JWST Calibration Summit, 31 March - 1 April 2009
NIRSpec Ground Calibration
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NIRSpec to undergo extensive cryogenic
performance verification and calibration prior
to delivery in 2010
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Campaign of ~2 month duration
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Exact date in flux (late flight ASICS)
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Associated facilities (IABG) and optical
ground support equipment (CLS and RCSS)
already in place
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On-going testing of NIRSpec Demonstration
Model (foreoptics only) serving as shakedown of facility and OGSE
JWST Calibration Summit, 31 March - 1 April 2009
Thermal Vacuum Facility
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Located at IABG
near Astrium in
Munich
Thermal
performance of
facility verified
Testing of CLS
on-going
Vacuum Tank
Vacuum Tank mated to CLS
JWST Calibration Summit, 31 March - 1 April 2009
Calibration Light Source (CLS)
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Primary optical
stimulus
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60 cm integrating
sphere fed by number
of continuum and line
sources
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Exit aperture mimics
JWST pupil at FSM
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Extended source
covering full FOV
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Pinhole mask
simulates multiple
point sources
Calibration Light Source (CLS)
Integrating Sphere
Light Sources
JWST Calibration Summit, 31 March - 1 April 2009
Radiometric Calibration Spectral
Source (RCSS)
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Radiometric
calibrated point
source on X,Y
translation table
Simulates OTE
image
Used to map MSA
slit function etc.
Challenge of
absolute NIR
calibrations being
appreciated...
1.5 mm
M2 mirror with
OTE shape and
central bore
Radius of 75 ì m
RCSS M2 Pupil Mirror
Integrating Sphere
Offner Housing
JWST Calibration Summit, 31 March - 1 April 2009
Plans
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Contents of Calibration Plan in place
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Wavelength and photometric all modes
Optical distortions
MSA slit function mapping
Simulate Target Acquisition procedure
(Monochromatic flats from detector team?)
etc
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Verify Instrument Model and reduction and
calibration approach, i.e. “play and practice”
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Too early to discuss detailed format of data
products
JWST Calibration Summit, 31 March - 1 April 2009