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  • This doesn't do much to address contamination
  • This mixes together wavelength and position more than a forward-modeling approach. 
  • Uncertainties are likely to be quite misleading

Simulation/Model based extraction of 1D spectrum for perfectly registered and calibrated data taken at several different orientations

Story: As a careful observer, I have taken my data at several different orientations with direct images as well. I would like to extract 1D spectra taking advantage of the observed morphology of the source in the direct image, and a first guess at its spectrum and that of the sources that may be overlapping.

What do I need as inputs?

  • Direct and slitless images with perfect WCSs
  • catalog information (coordinates, magnitudes ...)
  • Exposure times?
  • Noise model? Or components of the noise model (gain, exptime, read noise, subtracted background)?
    • Or is this already in an uncertainty array?
  • Detector signatures already removed (e.g. CALWEBB_DETECTOR1)
  • Identification of the pixels in the direct image corresponding to "the source" (e.g. from a segmentation map)
  • Identification of any pixels in the direct image corresponding to contaminating sources

What does this step do for me?

  • Maps pixels in the direct image to x,y, wavelength 
  • Folds the model spectra through the instrument response 
    • for the target of interest and the contaminants
    • for each orientation
  • Fits the models to the data
    • Somehow? 
      • How do we specify parameters to vary?
      • What do we use as the merit-function for the fit? 
      • How do we weight the data?
      • What do we use as the optimizer?
      • How do we calculate uncertainties?
  • Accumulates some kind of contamination flag at each wavelength

Why would I not want to do this?

  • I might be impatient (see first story), or only interested in a specific feature.
  • I might instead be searching for isolated emission lines

Epics

Identify and match data sets

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