elongated core ellipticals
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liometopum
I see these 'fuzzy ellipticals' containing elongated cores, from time to time. It is similar to Image AGZ0003em4 and AGZ00041zh which are closer and have more detail
These 'elongated core ellipticals' .... maybe we chould note them as possible lenticulars? They are not standard ellipticals.
Is it important to note?
Ideas?
Posted
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JeanTate
in response to liometopum's comment.
"True" ellipticals are not too far out of round, as measured by 'ellipticity'; of the three, the last one (AGZ00041zh) is clearly too far (Buta 2011 - "Galaxy Morphology" - is a great resource! He has another arXiv preprint with the same name; I'm not sure how different they are). So it's not an elliptical.
The second one (AGZ0003em4) has what looks like an edge-on disk; this too is not an elliptical.
The way to distinguish between ellipticals and lenticulars is, traditionally, whether the intensity profile is closer to a deVaucouleurs (elliptical) or exponential ('disk') (the intensity profile is the radial surface brightness, appropriately averaged). In most lenticulars, there are two components, a 'bulge' and a 'disk'; classical bulges are the same as ellipticals (deVaucouleurs profile), but some are 'pseudobulges' (i.e. they have a radial profile quite different from a deVaucouleurs one). Bulges in disk galaxies are almost always close to 'round'. If the galaxy has a bright nucleus - e.g. an AGN - this is, effectively, a point source in the center, and messes up the many automated bulge/disk decomposition catalogs out there (e.g. Meert+ 2013)*.
Is it important to note?
For you own research, certainly! For GZ, I have no idea.
*this is rather over-simplified; the Buta papers explain it all in much more detail.
ETA: I had a nice long response to your earlier post (Comments, etc), but somehow I pressed the wrong key, and it all vanished 😦Posted
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liometopum
Thanks JeanTate. I printed the larger of the two papers (174 pages), and am reading it now.
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