M49 - big image with 2-part extrapolation method

This is modelled (COPIED) from the M87e analysis...

First we follow the methods used on the smaller M87 image analysis (here), but on the largest/newest image of M49:


The plan:
Make a total mask (MTM.pl), which consists of:
    final star mask () Mbad.pl
    hand mask ()       Mhand.pl
    OBJ mask ()       Mr38sP1.pl
    UN mask ()        Mcent80.pl [80" radius circle unmasked]
Use this mask and run ellipse to fit the galaxy [stop at SMA=1300px, step=0.2, start at 40px center can vary, no limits on grad.rel.err. or flagged]
                                     [note, to use ellipse, each time you have to be sure you have an image M.fit (instead of .fits) and put the desired mask into M.pl, and it will be used properly]
Use bmodel to generate a model of the fit
Subtract this model off of the original image
Run OBJ mask on this image -- makes OBJmask #2
Make a new total mask (MTM2.pl), which consists of
    final star mask
    hand mask
    OBJmask #2 (from above) -- this makes it an iterative process



UN-masks:



Real fit and artdata/extrapolated fit
  

Comparing/seaming the real galaxy with the simulated:                                                            Close-up



And the final subtraction:
[Msubtract.fits]             (bigger versions further down)             (fits version and region file for rings)
                                                 if you want to see IDs/etc for these objects use NED regions file

(cut radius is the teal line)



binned with rmed i=3, o=5  [Msubtract35.fits]

(cut radius is the teal line)

 














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