ARG0003qrg: host has bright nucleus but not an AGN spectrum
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by JeanTate
In ARG0003qrg: zsp 0.281 host SDSS J085749.80+013530.3 has a bright nucleus, like an AGN:
Yet its spectrum is boring, like that of a normal elliptical with fading emission ... except that it's ~white, not at all red! 😮
Strange, no?
Posted
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by ivywong scientist, admin
Many AGN have large bulges so the brightness is coming from the large concentration of stars in the centre of this galaxy. If you were to fit a radial profile to this galaxy, I'm pretty sure that you'll get a fit with a Sersic index of 4, typical for an elliptical.
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by JeanTate in response to ivywong's comment.
Thanks Ivy.
Well, to me, the SDSS image has all the hallmarks of an AGN:
- the nucleus is 'star-like'
- it's white (the nuclei of ellipticals are rarely white)
- there's a pinkish shade on one side (AGNs with clearly resolved host galaxies almost always produce strange color effects in SDSS images)
If you were to fit a radial profile to this galaxy, I'm pretty sure that you'll get a fit with a Sersic index of 4, typical for an elliptical.
I've been meaning to get back to my Linux box, and run GALFIT over quite a few galaxies; thanks for the motivation to actually do that! 😃
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