Software Modelling of IFU Spectrometers

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Software Modelling of IFU Spectrometers

• Nuria P. F. Lorente
• UK Astronomy Technology Centre
• Royal Observatory, Edinburgh, UK

Alistair C. H. Glasse, Gillian S. Wright (UK ATC,
JWST-MIRI), Suzanne Ramsay Howat (UK ATC, KMOS),
Chris J. Evans (UK ATC, EELT)
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Why do we need instrument simulators?
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Why do we need instrument simulators?

• Increasing scale and complexity of telescopes and
  instruments with time

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Why do we need instrument simulators?

• Increasing scale and complexity of telescopes and
  instruments with time
• We need to know how design and construction
  changes may potentially affect the science we can
  do with the instrument

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Why do we need instrument simulators?

• Increasing scale and complexity of telescopes and
  instruments with time
• We need to know how design and construction
  changes may potentially affect the science we can
  do with the instrument
• Development of data reduction and analysis
  software requires test data

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Why do we need instrument simulators?

• Increasing scale and complexity of telescopes and
  instruments with time
• We need to know how design and construction
  changes may potentially affect the science we can
  do with the instrument
• Development of data reduction and analysis
  software requires test data
• An understanding of the data products will help
  in designing effective calibration strategies

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Why do we need instrument simulators?

• Increasing scale and complexity of telescopes and
  instruments with time
• We need to know how design and construction
  changes may potentially affect the science we can
  do with the instrument
• Development of data reduction and analysis
  software requires test data
• An understanding of the data products will help
  in designing effective calibration strategies
• Synthetic data products are an effective
  communication tool in a distributed scientific
  and engineering environment

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JWST-MIRI MRS

• Launch in 2013
• Positioned at L2
• 4 instruments on board

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JWST-MIRI MRS

• Collaborative project between
• Consortium of 21 institutes under ESA
• NASA
• Imager, coronograph, low-resolution
  spectrometer, IFU medium resolution spectrometer

• Launch in 2013
• Positioned at L2
• 4 instruments on board

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JWST-MIRI MRS

• 4 spectral channels (5 28 microns)
• FoV 3.70x3.70arcsec 7.74x7.93 arcsec
• Spectral resolution 3000

• One IFU slicer per channel
• All channels are observed simmultaneously
• Dichroic filters divide each IFU channel into 3
  sub-bands
• Data from pairs of channels are captured on two
  1024x1024 pixel detectors
• Expected sensitivity 1.21e-20 Wm-2, 6.4microns,
  5.610e-20 Wm-2 at 22.5 microns

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Specsim Modelling the Field of View
Specsim GUI
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Specsim Modelling the Field of View
Specsim GUI
Sky Background
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Specsim Modelling the Field of View
Specsim GUI
Targets
Sky Background
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Specsim Modelling the Field of View
Specsim GUI
Targets
Sky Background
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Specsim Modelling the Field of View
Specsim GUI
Targets
Sky Background
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Specsim Modelling the Field of View
Specsim GUI
Targets
Sky Background
Sky Model
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Specsim Modelling the IFU Spectrometer
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Specsim Modelling the IFU Spectrometer
Transmission Function Definitions
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Specsim Modelling the IFU Spectrometer
Transmission Function Definitions
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Specsim Modelling the IFU Spectrometer
Cosmic Rays Noise Exposure Length
Transmission Function Definitions
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Specsim Modelling the IFU Spectrometer
Cosmic Rays Noise Exposure Length
Transmission Function Definitions
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JWST-MIRI MRS
Modelling Observations of a YSO
(Glasse et al., in prep. 2007)
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JWST-MIRI MRS
Modelling Observations of a YSO
Spitzer IRS spectrometer (Lahuis et al., 2006)
(Glasse et al., in prep. 2007)
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JWST-MIRI MRS
Modelling Observations of a YSO
Spitzer IRS spectrometer (Lahuis et al., 2006)
"IRS46 at 875 pc" N_TARGETS 1 "Dither_A" 0
0.485 1.01 N_CONT 2 0 0.015 700.0 0 0.002
160.0 N_BROAD 2 0 -0.001 15.2 0.30 1
-0.014 N_NARROW 360 12.02300 -0.245
NL1" 12.03510 -0.023 NL2" ...
(Glasse et al., in prep. 2007)
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JWST-MIRI MRS
Modelling Observations of a YSO
Spitzer IRS spectrometer (Lahuis et al., 2006)
"IRS46 at 875 pc" N_TARGETS 1 "Dither_A" 0
0.485 1.01 N_CONT 2 0 0.015 700.0 0 0.002
160.0 N_BROAD 2 0 -0.001 15.2 0.30 1
-0.014 N_NARROW 360 12.02300 -0.245
NL1" 12.03510 -0.023 NL2" ...
Point source
Black-body continuum
CO2 Gaussian absorption feature, and silicate
spectrum
360 narrow absorption lines (HCN etc.)
(Glasse et al., in prep. 2007)
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JWST-MIRI MRS
Modelling Observations of a YSO
Spitzer IRS spectrometer (Lahuis et al., 2006)
Specsim synthetic spectrum
"IRS46 at 875 pc" N_TARGETS 1 "Dither_A" 0
0.485 1.01 N_CONT 2 0 0.015 700.0 0 0.002
160.0 N_BROAD 2 0 -0.001 15.2 0.30 1
-0.014 N_NARROW 360 12.02300 -0.245
NL1" 12.03510 -0.023 NL2" ...
Point source
Black-body continuum
CO2 Gaussian absorption feature, and silicate
spectrum
360 narrow absorption lines (HCN etc.)
(Glasse et al., in prep. 2007)
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JWST-MIRI MRS
Modelling Observations of a YSO
Simulated detector image
Simulated white-light images
(Glasse et al., in prep. 2007)
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VLT - KMOS

• NIR multi-object IFU spectrometer
• 3 identical channels
• 8 IFUs per channel
• 14 slices of 14 pixels per IFU
• 3 spectrographs
• 2048 x 2048 pixel detector images

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VLT - KMOS
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VLT - KMOS

• White-light image of the galaxy

• Portion of the detector image
• Note the spectral line and the galaxy continuum

• Image of the galaxy at the wavelength of the
  emission line

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E-ELT
Investigating the effect of adaptive optics on
image quality
Simulated field of view
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E-ELT
Investigating the effect of adaptive optics on
image quality
Seeing-limited PSF
Simulated field of view
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E-ELT
Investigating the effect of adaptive optics on
image quality
Seeing-limited PSF
Simulated white-light image, with no AO correction
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E-ELT
Investigating the effect of adaptive optics on
image quality
Ground-layer correction PSF
Simulated field of view
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E-ELT
Investigating the effect of adaptive optics on
image quality
Ground-layer correction PSF
Simulated white-light image with ground-layer
correction
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E-ELT
Investigating the effect of adaptive optics on
image quality
Laser Tomography PSF
Simulated field of view
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E-ELT
Investigating the effect of adaptive optics on
image quality
Laser Tomography PSF
Simulated white-light image with laser-tomography
correction
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E-ELT
Investigating the effect of adaptive optics on
image quality

• Seeing-limited field

• Ground layer correction only

• Laser-tomography