sunkit-spex
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sunpy
Add albedo correction
Describe the feature
A few people have been asking if we have implemented the albedo correction similar to OSPEX
Proposed solution
No response
I think that would be an excellent addition. I believe OSPEX implements it as a “pseudo-model” but it shouldn’t be too hard to add if we look up the proper equations.
This has been on my to-do list for a while, I've just never been able to get around to it properly.
I think OSPEX does it via altering the response matrix before the fit and I think the main files to look at are drm_albedo.pro and drm_correct_albedo.pro (found here with some description).
Instructions on how the user interacts with this in OSPEX and some history is here.
Yea those sav files are nightmare fuel do we have any idea how they were generated? @KriSun95 I think you are correct about the current implementation/approach here's the relevant paper but not clear if that the best way or have a model chain physical-model->albedo-model->SRM
@samaloney, I think your idea of physical-model->albedo-model->SRM makes more sense to me. I don't like the idea of editing the response any more than we really need to while having the correction as a model will help keep things transparent and make it easier to apply to different data too, I'd imagine.
For RHESSI the albedo correction is included as part of the DRM, the logic being that it's not the observed spectrum I_O you want to fit but the emitted I_E where I_0=I_E + I_A. At the GX_SIMULATOR meeting and found out Edward/Gelu have implemented the Albedo correction as an addition to the model spectrum so we should be able to use the same approach https://github.com/Gelu-Nita/GX_SIMULATOR/blob/d772a411705ceed9db2a5b6eadfa14cd5dda190f/userslib/xray/xray_tt_albedo.pro
Green function matrices are now available in JSON format (also as IDL SAVE files) https://github.com/edkontar/albedo
@edkontar thanks, Eduard! this will be very useful for albedo corrections going forward.
would you like to help implement the corrections in Python?
would you like to help implement the corrections in Python?
Yes, I would be happy to help
I have a draft PR open which uses the sav files from SSW in #161
What we eventually need is the ability to generate the "green's matrices"