Class-based instrument pack

PAHFIT / pahfit

Model Decomposition for Near- to Mid-Infrared Spectroscopy of Astronomical Sources

https://pahfit.readthedocs.io/

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Class-based instrument pack #182

Open els1 opened 2 years ago

els1 commented 2 years ago

Create an example of a class-based instrument pack to explore this venue.

jdtsmith commented 2 years ago

In implementing this, I'm rethinking. I strongly suspect that each and every one of the instrument channels will in the end just implement a fwhm(wavelength) polynomial model with say 4 parameters max (and likely 2 or even 1). If we think that's the case, then a simple table with rows like:

instrument channel wave_min wave_max p0 p1 p2 p3

would totally suffice. Thoughts? We could take that simple shortcut and then if need be expand it out down the road.

karllark commented 2 years ago

We should make sure this works for MIRI/NIRSpec before deciding.

jdtsmith commented 2 years ago

Good thought. Can you get your hands on the expected FWHM(wavelength) line spread function tables for the relevant JWST NIRSPEC + MIRI channels/gratings?

Other things I could imagine coming to an instrument pack:

Turning on a "small amount" of wavelength offset for the entire sub-spectrum (e.g. if NIRSPEC wave-cal is a wee bit off).
what else?

karllark commented 2 years ago

See Fig. 3 at https://jwst-docs.stsci.edu/jwst-mid-infrared-instrument/miri-observing-modes/miri-medium-resolution-spectroscopy.

jdtsmith commented 2 years ago

Looks like we'll be able to get away with a piecewise polynomial. I'll go that route for now for simplicity, and if we have to make it more complex down the road we can do so. The main thing to preserve is how to "tag" a spectrum with its instrument on a conserved name.