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moustakas / legacyhalos

Code and papers for a multi-faceted study of the baryonic content of dark matter halos in Legacy Survey imaging.
MIT License
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redo Tractor fitting after custom sky-subtraction #65

Closed moustakas closed 5 years ago

moustakas commented 6 years ago

In the customphot branch the new algorithm / procedure is:

  1. Use the default pipeline (which includes spline sky-subtraction) to generate custom coadds centered on each cluster and fit (with Tractor) every source.
  2. Mask sources aggressively (including the central galaxy, out to 150 kpc) and re-estimate the sky background as a constant.
  3. Generate new, custom coadds with the new sky subtracted.

In the last step, let's also include refitting all the sources with the Tractor. It'll add more computational time, but it'll ensure that the satellite photometry also benefits from the corrected sky background.

That said, this algorithm may be sub-optimal if there's significant ICL...

moustakas commented 5 years ago

Also need to write out an updated Tractor catalog with the central galaxy removed, which, at minimum, we need to handle the SDSS mosaics properly (#86).

Alternatively, could push the code in coadds.custom_coadds for isolating the central to its own function and then use that in sdss.custom_coadds. One less file!

moustakas commented 5 years ago

Done in #94.