Crossmatch Catalog Part III

In Part I and Part II I was looking at how well the SE++ catalog recovered the input galaxy properties.

Here I’m looking more closely at the images, and trying to verify the galaxies have the right RA and dec assigned.

Plotting the galaxies on top of the image

The easiest way to compare the sources to the image is to make region file from catalog, then just load in DS9. I drew each galaxy as an ellipse, with its size as the half-light radius, the shape of the ellipse scaled according to the galaxy ellipticity. I used the position angle to give a tilt to the ellipse.

Here is the whole catalog, with the B1 tile shown underneath:

It looks like the SE++ catalog only contains B tiles (and is missing B9).

Here is a zoom-in:

I think it looks pretty decent, but there are some obvious mis-identified galaxies.

Updated ellipticity

One thing I realized while putting this together was that I was using the wrong “ellipticity” parameter in the SE catalog. Here’s an update of the recovered versus input parameter plot:

To-Do

Here’s what’s left on my to-do list for this:

Figure out why some tile file sizes are different (different “PXSCLRT” parameters)
See if Marko will rerun SE++ with updated F444w catalogs (and for full field)
Solidify cross-matching procedure
Post these results, see what people think (it will be easier to conclude things once I have some redshift information)

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