how are cataloged the presence of only one jet ?
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roder53
I exclude the radio source at the top of the image, because it does not have a correspondent in the infrared.
The other two radio sources have only one jet, one nice and simple and the other big.
Question: how are cataloged the presence of only one jet?Posted
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JeanTate
in response to roder53's comment.
To me, this is an asymmetric #doublelobe, with a faint core; the brighter lobe (SW) also has a faint jet leading to it, as can be seen in the FIRST image.
The faint core is an IR object, very likely the z_ph ~0.66 SDSS J091454.32+192519.6.
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roder53
Ok, thanks a lot. But I understood: the weak core is a bright object, galaxy and its luminosity is weak for a considerable distance.
The question is: what are these jets?
My impression: it is not a black hole and then what are the radio images?Posted
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JeanTate
in response to roder53's comment.
As I understand it, the jets are also plasma; what we see is electromagnetic radiation in the radio part of the spectrum, produced by the interaction of the very fast particles emitted by/in the polar jets of the AGN (active galactic nucleus), powered somehow by the SMBH, and the thin plasma through which it travels (in a tiny handful of objects, the jets are also visible in the optical and/or x-ray part of the the EM spectrum).
At the distance of this object, and with the resolution of FIRST, even the host galaxy - which contains, at its center, the AGN - is just a 'point'; even for the closest AGN and highest resolution - M87 - the 'engine' (which is where the jets originate) is still just a point (though the galaxy is, obviously, well-resolved).
There are a whole lot of GZ blog posts on radio galaxies, jets, lobes, etc; perhaps the best two to start with are The Curious Lives Of Radio Galaxies – Part One and
The Curious Lives of Radio Galaxies – Part TwoPosted
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roder53
thank you very muchis now more clear
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