Radio Galaxy Zoo Talk

J1216+0709 : A radio galaxy with three episodes of AGN jet activity

  • ivywong by ivywong scientist, admin

    http://arxiv.org/abs/1605.05821

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  • zutopian by zutopian

    SDSS image available, as mentioned in the paper.:

    enter image description here
    SDSS J121632.42+070955.7
    http://skyserver.sdss.org/dr9/en/tools/explore/obj.asp?ra=12:16:32.42&dec=+07:09:55.8
    z= 0.136 (spectroscopic)

    J1216+0709 : A radio galaxy with three episodes of AGN jet activity
    Authors: Veeresh Singh, C.H. Ishwara-Chandra, Preeti Kharb, Shweta Srivastava, P. Janardhan

    We report the discovery of a ‘Triple-Double Radio Galaxy (TDRG)’ J1216+0709 detected in deep low-frequency Giant Metrewave Radio Telescope (GMRT) observations. J1216+0709 is only the third radio galaxy, after B0925+420 and Speca, with three pairs of lobes resulting from three different episodes of AGN jet activity. (...)

    (Submitted on 19 May 2016)
    http://arxiv.org/abs/1605.05821

    REFERENCES:

    Three episodes of jet activity in the FRII radio galaxy B0925+420
    Authors: C. Brocksopp (MSSL/UCL), C.R.Kaiser, A.P. Schoenmakers, A.G. de Bruyn

    We present Very Large Array images of a "Double-Double Radio Galaxy", a class of objects in which two pairs of lobes are aligned either side of the nucleus. In this object, B0925+420, we discover a third pair of lobes, close to the core and again in alignment with the other lobes. This first-known "Triple-Double" object strongly increases the likelihood that these lobes represent mutiple episodes of jet activity, as opposed to knots in an underlying jet. (...)

    (Submitted on 28 Sep 2007)
    http://arxiv.org/abs/0709.4548

    Radio Zoo Talk discussion:
    ARG000128s / FIRSTJ092910.4+414646 - B0 925+420, so called triple - double
    https://radiotalk.galaxyzoo.org/#/boards/BRG0000006/discussions/DRG00005go

    ‘Speca’ -SPiral-host Episodic Cluster-dominant AGN:

    Discovery of a spiral-host episodic radio-galaxy
    Authors: Ananda Hota (1), S.K. Sirothia (2), Youichi Ohyama (1), C. Konar (1), Suk Kim (3), Soo-Chang Rey (3), D.J. Saikia (2), J.H. Croston (4), Satoki Matsushita (1)

    We report the discovery of a unique radio galaxy at z=0.137, which could possibly be the second spiral-host large radio galaxy and also the second triple-double episodic radio galaxy.(...)
    The source was identified from SDSS, GALEX, NVSS and FIRST survey data but we also present follow up optical observations with the Lulin telescope and 325 MHz low frequency radio observations with the GMRT. (...)

    (...)

    ACKNOWLEDGMENTS
    We are grateful to the referee, William Keel, for helpful comments. (...)

    (Submitted on 24 Jul 2011)
    http://arxiv.org/abs/1107.4742

    Below "Radio Zoo Talk" discussion about Speca contains a SDSS overlay image.:
    https://radiotalk.galaxyzoo.org/#/boards/BRG0000002/discussions/DRG00007i1

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  • JeanTate by JeanTate

    @ivywong, @zutopian: Thanks for posting about this! 😃

    I wonder how many "Triple-Double Radio Galaxy (TDRG)" there are in the fields/objects tagged here in RGZ Talk as #restarted?

    Posted

  • ivywong by ivywong scientist, admin

    Yep, as per usual, feel free to hunt for these extreme cases here or in a new thread. We will of course help you along the way as much as we can since that is what we are all here for 😃

    Note that Hota has his own citizen science project called RAD@Home based in India (https://www.facebook.com/groups/RADathome/) searching for these unusual extreme sources.

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  • Dolorous_Edd by Dolorous_Edd

    Something like? But, yeah, separate thread will be good

    https://radiotalk.galaxyzoo.org/#/subjects/ARG0002hll

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  • zutopian by zutopian in response to ivywong's comment.

    Note that Hota has his own citizen science project called RAD@Home based in India (https://www.facebook.com/groups/RADathome/) searching for these unusual extreme sources.

    Please be informed, that I mentioned RAD@Home in below discussion about "Speca" four days ago.:
    https://radiotalk.galaxyzoo.org/#/boards/BRG0000002/discussions/DRG00007i1

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  • ivywong by ivywong scientist, admin

    Thanks @zutopian for the heads-up. Sorry I forgot to mention your Speca discussion where you brought this up too.

    Posted