spiral galaxy with doublelobe emission

• by WizardHowl

  #doublelobe emission seems to originate from SDSS J122640.22+253855.5 Z_sp=0.134 with a face-on spiral morphology. There are no other optical candidates that might signify emission from a background source.

  Posted January 17, 2014 2:52 PM

• by JeanTate in response to WizardHowl's comment.

  Here's that galaxy, in SDSS:

  

  Its GZ1 morphology is "uncertain" ... it certainly seems to have a bulge/nucleus, and there seems to be some sort of chaotic structure outside that, but I myself don't see anything that I'd call spiral arms. The colors are odd, hinting at regions of starformation, even dust-shrouded starbursts (like Arp220 perhaps)? If so, it may be a late-stage merger.

  The SDSS spectroscopic pipeline classifies the spectrum as STARFORMING; it's certainly got some nice strong (narrow) emission lines!

  Posted January 17, 2014 5:54 PM

• by DocR scientist

  Looks like a pretty nice case to me. Pretty clear disk emission even if no coherent spiral structure.

  Posted January 18, 2014 1:44 PM

• by WizardHowl

  Could this also be a disk galaxy?

  http://radiotalk.galaxyzoo.org/#/subjects/ARG0003qg8

  If the bright IR source directly in between the two lobes is indeed the host of the radio emission, this is SDSS J112526.53+014301.5 Z_sp=0.434. In spite of its orange colour, it has an elongated shape with a central bulge and the spectrum shows strong narrow emission lines: this is the signature of a disk galaxy? (From our line of sight spiral structure would not be visible as it seems almost edge-on)

  Posted January 20, 2014 4:14 PM

• by WizardHowl

  Improbable though it seems, I have found two additional candidates today, although there is of course the caveat that I may not have correctly identified the host galaxy. They are quite different objects:

  http://radiotalk.galaxyzoo.org/#/subjects/ARG00007yo

  My host candidate here is SDSS J083136.46+574545.9 Z_sp=0.726 the spectrum seems in between an elliptical and disk but has more and stronger emission features, altjhough this could just be because it has a lower resolution; this is a very faint object after all and only appears as a red blob.

  http://radiotalk.galaxyzoo.org/#/subjects/ARG00027yg

  The host for the right hand source here seems to be SDSS J170525.98+221617.9 Z_sp=0.048 a smooth spiral but with a spectrum more closely resembling an elliptical. Maybe it could be an elliptical that has been disturbed by an encounter (with the larger elliptical next door that also is a radio source) and now has a spiral shape? If so then it is not a 'true' spiral but the recent blog post about red spirals found in Galaxy Zoo Hubble suggests that the view of which galaxies may really be disks may be changing anyway, which will impact radio classifications... (discussion for another day...)

  Posted January 20, 2014 7:40 PM

• by WizardHowl

  Today I also found two candidates and am adding them to this thread to keep track of them - they are both in the same image and at the same redshift of Z_sp=0.095, so their morphology is clearer and their spectra cleaner:

  http://radiotalk.galaxyzoo.org/#/subjects/ARG0002j29

  almost edge-on disk SDSS J135817.73+171236.7

  barred spiral SDSS J135818.74+171300.6

  The barred spiral has much weaker emission that barely generates a contour and both seem to be corejets, although it is also possible that the stronger source is a triple and the barred galaxy just has weak activity near its core; the orientation makes it ambiguous and without seeing detail in the jets the triple scenario is more likely as it invokes only one source rather than two.

  Posted January 21, 2014 9:34 PM

• by WizardHowl

  Just found a convincing-looking candidate, although it does not have a spectrum.

  http://radiotalk.galaxyzoo.org/#/subjects/ARG00022wh

  face-on disk shape with hint of spiral structure SDSS J112811.63+241746.9 Z_ph~0.16

  The radio emission is a doublelobe shape. There are no other optical candidates that look properly positioned to be the host; it is quite an isolated galaxy in IR/optical with the nearest source ~15" NNE, which looks to be too far to generate such symmetrical lobes. In fairness, this source is SDSS J112811.86+241800.1 Z_ph~0.6 and is probably an elliptical galaxy, although SDSS is unable to resolve its shape.

  Posted January 30, 2014 3:00 PM

• by WizardHowl

  Another candidate for a disk with radio lobes today ... either these are not as rare as I'd thought, or we're really lucky to have so many in the survey, or I'm just plain wrong on most/all of them (this is the most likely, in fairness). In this case, I'm at least convinced the galaxy is a disk and it has a clean spectrum with huge OII/III, Halpha and Hbeta emission lines and the continuum shape to support that assertion. There's always the possibility of a source being behind its disk and out of sight, of course, but there's nothing else that looks properly positioned to be the host.

  http://radiotalk.galaxyzoo.org/#/subjects/ARG0002y6c

  NVSS shows diffuse radio emission extended SE to NW. SDSS J080217.94+112535.0 Z_sp=.060

  The FIRST signal is small and only shows a faint extension to the SE but the NVSS shows a larger region of emission, as if there are diffuse lobes or jets extending in a SE to NW direction. These are still faint but the symmetry combined with the hints of diffuse emission along this line from FIRST are what makes me suggest this as an interesting source.

  Posted January 31, 2014 4:26 PM

• by WizardHowl

  This candidate is 50/50 as I'm less sure of the source - but the alternative source of the hourglass is a small smudge of a galaxy at Z_ph~0.08 that may be about as unlikely to be the host as the edge-on disk seen here:
  http://radiotalk.galaxyzoo.org/#/subjects/ARG0002ozz

  This galaxy is SDSS J144040.41+144125.1 and has a photometric redshift estimate of ~0.32-0.42. It appears too elongated to be a lenticular elliptical. It would be easier to ascertain the ID of the host if the FIRST radio contours could be overlaid on top of the SDSS image but I do not know how to do this.

  Posted February 21, 2014 6:39 PM

• by WizardHowl

  Adding several potential candidates to this list where I think I'm sure of the source of radio emission but in these cases there is the potential for the galaxy to only be looking disk-shaped and to actually be spherical/elliptical.

  http://radiotalk.galaxyzoo.org/#/subjects/ARG00028nb -- no spectrum Z_ph~0.13-0.14 SDSS J142305.86+215735.5

  http://radiotalk.galaxyzoo.org/#/subjects/ARG0001kwr -- classed as QSO, Z_sp=0.125 SDSS J121659.93+323106.0

  http://radiotalk.galaxyzoo.org/#/subjects/ARG0003o7j -- dust lane? Z_sp=0.145 SDSS J022612.45+023307.4

  I accept it may require further/deeper observations in some cases to confirm matters one way or another regarding any of the objects in this list but to me they all look promising enough to report. Of these three, SDSS J121659.93+323106.0 would be interesting anyway as it appears to be a 'nearby' quasar with radio lobes where the host galaxy is clearly visible.

  Posted February 25, 2014 7:33 PM

• by JeanTate in response to WizardHowl's comment.

  

  FIRST+SDSS composite image of ARG00022wh, copied from the GZ forum OOTD.

  Posted February 26, 2014 2:08 AM

• by JeanTate in response to JeanTate's comment.

  Here is ARG0001zj8, as a composite FIRST and SDSS image (posted in the GZ forum OOTD thread on this topic):

  

  Posted February 26, 2014 3:33 AM

• by WizardHowl in response to JeanTate's comment.

  These composite images are just awesome. If only we had an optical survey as deep as the WISE survey... (extremely wishful thinking! and a lot of it would be empty space at those wavelengths...). I wonder how many of the more distant (radio) galaxies in SDSS are disk galaxies - there might be a lot more out there, purely from geometrical arguments; we can only reliably identify disks/spirals as such in the very nearby Universe (out to ~z=0.08 if I remember for GZ1 classifications?) and that's a much smaller volume than the region out to z~0.7 at the limits of SDSS....

  Posted February 26, 2014 10:54 AM

• by JeanTate in response to WizardHowl's comment.

  These composite images are just awesome.

  Glad you like them. 😃 Over in the GZ forum OOTD, I just posted my thanks to c_cld for helping me work out how to create them; I also briefly summarized how I actually do (not quite the same way as c_cld does).

  [...] we can only reliably identify disks/spirals as such in the very nearby Universe (out to ~z=0.08 if I remember for GZ1 classifications?) and that's a much smaller volume than the region out to z~0.7 at the limits of SDSS....

  It's a bit more complicated than that.

  For example, I've been hunting Huds (huge distant spirals) in SDSS for some time (see my Wednesday, 13th March, 2013: Galaxy #21 OOTD, for example), and have even written a couple of Letters about them*. If they're big enough, disk galaxies - even spirals - can be clearly identified in SDSS images out to z~0.4. On the other hand, a small spiral such as M33 would be hard to identify even at z~0.08.

  A redshift of ~0.7 is about the limit of SDSS for giant ellipticals; however AGN candidates can be identified by their colors, even if they appear as point sources (i.e. no different than stars), and BOSS spectra can easily confirm their AGN identity (as long as they're not too faint). And QSOs (quasars) by the thousand have been identified using SDSS spectra; I don't know what the max redshift of those is, but it's surely at least 2.

  *but I can't mention this, 😮 "it never should of been made available for us to use" (source); click here for A Letter about Letters.

  Posted February 26, 2014 9:05 PM

• by c_cld

  ARG0000x3e

  #doublelobe source ~ 4C 44.18 Seyfert_2

  class spec: starforming

  09 21 33.0 +44 13 44 z spec=0.247

  size 2.5' or 576kpc

  Posted March 1, 2014 8:37 PM

• by c_cld

  ARG0002oyw

  #hourglass

  host 1237661070863761563 10:44:34.63, +14:42:04.07 z spec 0.155

  size 1.82' or 855 kpc

  Posted March 2, 2014 2:30 PM

• by WizardHowl

  This irregular-looking smudge does not look at all like either an elliptical galaxy or a QSO and to me looks more like it might be a spiral/disk galaxy. It is SDSS J124256.34+101305.9 and sadly has no spectrum. It has photometric redshifts that do not agree well with each other (0.249 ± 0.0599 and 0.090 ± 0.0394), suggesting unusual colours. The radio emission is in a doublelobe configuration that appears slightly bent.

  http://radiotalk.galaxyzoo.org/#/subjects/ARG000328n

  Posted March 6, 2014 3:28 PM

• by JeanTate in response to WizardHowl's comment.

  SDSS J170525.98+221617.9, the nice face-on spiral in the center:

  

  Here it is overlaid with FIRST, in red (a fair bit of image processing, so it's more artist than scientific):

  

  Posted in Friday, 21 February, 2014: Very Strange Spirals? GZ forum thread, here.

  Posted June 10, 2014 10:48 AM

• by JeanTate in response to JeanTate's comment.

  A contour overlay version, ARG0001zj8:

  

  The automated SDSS spectroscopic pipeline classifies the spectrum - of the central 3" (diameter) - as STARFORMING:

  

  <>

  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 is the galaxy SDSS J122640.22+253855.5, near the ARG image (left; J2000.0). "z_sp" is the SDSS spectroscopic redshift of the galaxy in the center.

  Posted August 1, 2014 6:58 PM

• by JeanTate in response to JeanTate's comment.

  A contour overlay version, ARG00022wh:

  

  <>

  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 is the galaxy SDSS J112811.63+241746.9, near the ARG image (ARG00022wh; J2000.0). "z_ph" is an SDSS photometric redshift of the galaxy in the center.

  Posted August 1, 2014 7:12 PM

• by JeanTate in response to WizardHowl's comment.

  Adding several potential candidates to this list where I think I'm sure of the source of radio emission but in these cases there is the potential for the galaxy to only be looking disk-shaped and to actually be spherical/elliptical. [...]

  http://radiotalk.galaxyzoo.org/#/subjects/ARG0003o7j -- dust lane? Z_sp=0.145 SDSS J022612.45+023307.4

  I accept it may require further/deeper observations in some cases to confirm matters one way or another regarding any of the objects in this list but to me they all look promising enough to report.

  A contour overlay version, ARG0003o7j:

  

  The SDSS spectrum (aperture 3" in diameter, centered on the nucleus) is that of a heavily reddened normal spiral:

  

  <>

  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 is the galaxy SDSS J022612.45+023307.4, near the ARG image (ARG0003o7j; J2000.0). "z_sp" is an SDSS spectroscopic redshift of the galaxy in the center.

  Posted August 1, 2014 10:29 PM