Radio Galaxy Zoo Talk

Overlapping Radio & I.R..

  • Chinabob by Chinabob

    This seems to be a very good example of an overlapping Radio & I.R. source as you progress from radio to I.R., the two shapes align perfectly until you reach the max I.R. Is my reading correct?


  • JeanTate by JeanTate in response to Chinabob's comment.

    My guess - nothing more - would be that there are un-associated (independent? unrelated? what's the best technical term??) radio sources: the one in the center is, as you say, also an IR source; the other (upper-left) seems to have no counterpart IR source. The central source is, in SDSS, a yellow blob, likely a giant elliptical; if so, then it likely has an AGN, of the radio kind (albeit rather faint). It's impossible to tell - with data alone - if this is a core source, or looking-down-the-barrel kind (i.e. lobes, jets, and core are all aligned, from our POV). A radio astronomer may be able to tell these alternatives apart, especially if there's data on polarization, or x-ray/gamma-ray data ...

    In SDSS DR10, the central source is SDSS J161253.91+114125.0, a largish late-type galaxy with a BOSS spectrum (z=0.235, no sign of any AGN-like activity):

    enter image description here


  • DocR by DocR scientist

    Not sure which features you're looking at, and I'm not sure what "overlapping" means -- are we using it to designate random superposition of radio and IR as opposed to actual identification? That would be very hard to figure out in general. Or two radio sources that are in the same field? That is likely what's going on here.

    The central source here is likely AGN, slightly extended as noted by @JeanTate.

    The northern (left, east) compact radio emission has no IR counterpart.

    Then there is the low brightness radio emission in the south, too faint for contours. There is faint emission here also in NVSS, so this is real and associated with the IR source south of center.