Radio Galaxy Zoo Talk

ARG0002g0s - one or two radio galaxies? one clearly disk-like

  • JeanTate by JeanTate

    From the Suggestions for RGZ Objects to show with detailed FIRST contours overlaid on SDSS images thread, started by WizardHowl:

    http://radiotalk.galaxyzoo.org/#/subjects/ARG0002g0s one or two radio galaxies? one clearly disk-like

    I'd say one, and yes, the host is the disk-like SDSS J130140.93+183104.9 z_sp=0.146

    enter image description here

    Zooming in; perhaps SDSS J130140.27+183058.9 (right; z_ph 0.174 ± 0.0440/0.213 ± 0.1458) is a merger remnant, connected by a faint tidal tail?

    enter image description here enter image description here

    <enter image description here>

    Boilerplate: SDSS image per http://skyservice.pha.jhu.edu/DR10/ImgCutout/getjpeg.aspx, FIRST (red) contours derived from FITS file produced using SkyView with Python code described in this RGZ Talk thread. Image center per the ARG image (left; J2000).

    Posted

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

    Another really helpful overlay! These are simply great, not least because some of them have shown the source of emission to be something other than the suspected galaxies - removing false positives ('winnowing') without doing further observations is really useful as telescope time is so hard to come by. (Well, with LOFAR you would only be interacting with the database but that is unique).

    Interesting that this might be an interacting pair of galaxies. Once there's a sufficient number of good-looking cases it will be worthwhile checking what proportion are doing this. Perhaps the SMBH can only become active if the flow of gas around it is disrupted, which is more likely to happen with larger mergers. Or perhaps, like in our own spiral galaxy, the SMBH is surrounded by both stars and gas clouds and a merger disrupts the orbits (as a result of close encounters with either stars or gas clouds from the other galaxy) so that one or more stars have close encounters with the SMBH and are ripped apart, providing a lot more material that is then thrown out in the form of jets. The IR images I remember seeing of Sgr A* showing stars orbiting the Milky Way's SMBH show a number of stars very close by, within a LY I think, on very chaotic orbits that might easily be disrupted. This would not spin-up the SMBH anything like as much as a merger with another galaxy's SMBH, though, so I would not expect such powerful jets from the relatively less massive and slowly rotating SMBHs in spirals compared to ellipticals.

    Posted

  • JeanTate by JeanTate

    Here's the same overlap, with the addition of z_sp (of the galaxy in the center) on the image itself:

    enter image description here

    Boilerplate: SDSS image per http://skyservice.pha.jhu.edu/DR10/ImgCutout/getjpeg.aspx, FIRST (red) contours derived from FITS file produced using SkyView with Python code described in this RGZ Talk thread. Image center per the ARG image (left; J2000.0). "z_sp" is the SDSS spectroscopic redshift of the galaxy in the center.

    Posted

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

    Another overlay image, centered on the host:

    enter image description here

    Boilerplate: SDSS image per http://skyservice.pha.jhu.edu/DR10/ImgCutout/getjpeg.aspx, FIRST (red) contours derived from the FITS file produced using SkyView with Python code described in this RGZ Talk thread. Image center (J2000.0) is the galaxy SDSS J130140.93+183104.9; "z_sp" its SDSS spectroscopic redshift.

    Posted