Radio Galaxy Zoo Talk

An updated catalogue of giant radio sources

  • zutopian by zutopian

    An updated catalogue of giant radio sources.
    A. Kuźmicz, M. Jamrozy, K. Bronarska, K. Janda-Boczar, D. J. Saikia.
    (Submitted on 24 Sep 2018).

    We present a catalogue of 349 giant radio sources (GRSs including both galaxies and quasars). The database contains all giants known to date from the literature. (...)

    There is a list of the GRSs given in the paper.: Table 1: Pages 11-20.

    PS: I informed about this paper also in following discussion today.:
    Finding the Giants (NVSS)


  • sisifolibre by sisifolibre

    I see to @HAndernach in the acknowledgments, but I can't find any reference to RGZ. I hope he and his team is working in one catalogue including the giant candidates we have found here.

    In other hand I found that:

    "include radio sources of projected linear sizes larger than 0.7~Mpc"

    I usually only comment subjects where the linear size is larger that ~0.9 Mpc, because somewhere in this forum I read that only is a giant if is up to 1 Mpc. Perhaps I have let without collect dozens of subjects with size between 0.7-0.9 Mpc....

    To add more, I found this in wikipedia. Where they say that a giant must be larger than 2 Mpc, must be changed?


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

    He is acknowledged as follows.:

    We thank the reviewer Prof. H. Andernach for his very detailed and valuable comments that helped improve the paper significantly.

    I guess, that "reviewer" means "referee"! As far as I know, the editors of a journal ask a scientist to review a paper by other scientists ("peer review").

    I would suggest, that the catalogue should be crossmatched with Giant RSs found by RGZ volunteers!


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

    AFAIK If is a paper to publish in an academic journal the peer review must be done by other anonimous scientist, the reviewers should not be influenced by the authors.

    But perhaps this paper is only for ArXiv, a "repository", where the paper aren't really peer reviewed... Anyway I think the acknowledgement is by other kind of help given to authors.

    I'm sure that @HAndernach have crossmatched this catalog with our findings. I can remember this comment where he talk about 220 found by RGZ volunteers:

    I hope to have more info before the finish of actual RGZ, I hope not have to do a list by myself from the forum XDD. But you know... science go slow.... and is a good thing 😃


  • JeanTate by JeanTate

    It certainly is interesting, isn't it? 😃

    It's also very strange, in many respects.

    For example, in this GZ blog post ("The shoulder of Giants"), dated the last day of 2016, there are 432 giants (231 "in the literature", and 201 newly discovered in RGZ), considerably more than the 349 in the paper.

    Also, no reference to Banfield+ (2016) 😮 This too is covered in a GZ blog post ("Discovered galaxy cluster named after two citizen scientists"), as well as its own thread here. So much for "all giants known to date from the literature" 😄

    But perhaps this paper is only for ArXiv

    arXiv is a strange beast: its primary purpose is to serve as a "pre-print" repository, for (draft) papers that will, one day, be submitted to a peer-reviewed journal for publication. Instead, it has become much more than that, for example a place where copies of papers accepted for publication (but not yet published) may be posted too.

    For this paper, the Comment field contains "Accepted to publish in ApJS". 😮 😮 I guess someone, somewhere failed ... 😦


  • HAndernach by HAndernach scientist, translator

    I had been asked by Astrophysical Journal Supplement to referee the paper
    which I did rather carefully. I never mentioned any of the NEWLY discovered giants
    in Radio Galaxy Zoo, but there will be several dozen giants in their list that
    have been (re)discovered in RGZ, or discovered and published by other
    authors outside and independent of RGZ. There are still over 200 giants (larger
    than 1 Mpc) found in RGZ that the Kuzmicz paper does not include. This
    is more than enough for a detailed paper on the RGZ-based giants.
    For about 30 years GRGs were taken as those larger than 1 Mpc (H0=50), but
    later other authors argued that with H0=70 one should include objects
    larger than 0.7 Mpc. If we did that, RGZ would have discovered well over
    400 such objects, and I am still monitoring radiotalk to look for new ones
    (none larger than 1 Mpc for about 3 months). The definition in wikipedia is equally arbitrary and
    would correspond to a minimum of 1.4 Mpc for H0=70, which I haven't seen in
    any scientific paper as yet.


  • sisifolibre by sisifolibre

    Thank you very very much for the update and the answers! It hadn't occurred to me that papers still can consider H0=50 😮.

    I am still monitoring radiotalk to look for new ones (none larger than 1 Mpc for about 3 months).

    I hope you follow too the thread Finding the Giants (NVSS). Although I guess you don't wanto to comment all the possible candidates, there are lots of subjects without your comments. This mean that these candidates from the last 2 months (some of them comented by you) finally aren't real giants? Thank you again for your answers and patience.


  • HAndernach by HAndernach scientist, translator

    Thanks for the link to "Finding the Giants (NVSS)". I have now
    responded to a few of the latest suggestions (Sept. 2018). Most
    of them seem speculative as there is no radio core, nor are there
    clear morphological features (like emission from the supposed hotspots
    pointing back to the other hotspot) that would make them good
    candidates. We need deeper surveys for this, and don't forget...
    a large fraction of these compact sources (supposed to be hotspots)
    is so far away that their optical counterpart has not been detected
    in current optical and IR surveys.