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LM-SAL / aiapy

Python library for AIA data analysis
https://aiapy.readthedocs.io/en/stable/
BSD 3-Clause "New" or "Revised" License
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Why is there a discharge floor in the gain calculation #116

Closed nabobalis closed 8 months ago

nabobalis commented 1 year ago

In GitLab by @wtbarnes on Jan 12, 2023, 14:24

When converting from photons to electrons in the response function, there is a line that imposes a limit on no less than 1 electron per photon,

https://gitlab.com/LMSAL_HUB/aia_hub/aiapy/-/blob/main/aiapy/response/channel.py#L373-375

This is not correct as there is no guarantee that a photon need produce an electron in the system. I carried this condition over from the following line in the IDL script for calculating the AIA response, aia_bp_parse_effarea.pro,

elecperphot = (evperphot * thisfullstr.elecperev) > 1

Importantly, this line has no effect as for the wavelength ranges relevant to this instrument, the electron-per-photon conversion is always > 1. However, I think this line should be removed. I'd also like to understand why this line is in the IDL code in the first place as perhaps there is something I'm missing or perhaps I misinterpreted the original intent of this condition when translating the code from IDL to Python.

nabobalis commented 10 months ago

In GitLab by @wtbarnes on Sep 2, 2023, 11:20

mentioned in commit cfd7e3bef94019b7f8763e3b32d8996f4bcc9f6b