A Strong Gravitational Lens Candiate from 2004

by Budgieye moderator

enter image description here

Galaxy Zoo http://talk.galaxyzoo.org/#/subjects/AGZ000825u

An arc candidate in GOODS ACS field Fassnacht 2004 http://iopscience.iop.org/1538-4357/600/2/L155/fulltext/

SDSS J123800.36+621813.1 http://skyserver.sdss.org/dr12/en/tools/explore/Summary.aspx?id=1237655369825845831

http://ned.ipac.caltech.edu/cgi-bin/ex_refcode?refcode=2004ApJ...600L.155F

Posted May 12, 2015 8:27 AM

Here's different images of the same galaxies from the article. I've seen about 5 galaxies from this article and commented on some, there hasn't been any additional published follow up on the ones I've seen with newer articles in NED.

lens cand1
lens cand2

Here's the full list if anyone is interested.
http://www.stsci.edu/science/goods/lensing/Lenscands/lenscands.html

Posted May 12, 2015 9:13 AM

by Budgieye moderator

It is good to have a record. Is there a discussion linking the GOODS list with the AGZ... numbers?

Posted May 12, 2015 9:26 AM

by ramberts

Lens Cand

Here's 2004 image with scale

2004 image

http://talk.galaxyzoo.org/#/subjects/AGZ000802q

Posted May 12, 2015 9:32 AM

by ramberts in response to ramberts's comment.

Lens Cand

2004 image

2004

http://talk.galaxyzoo.org/#/subjects/AGZ00085ll

Posted May 12, 2015 9:36 AM

by ramberts in response to ramberts's comment.

Lens Cand

2004 image

2004

http://talk.galaxyzoo.org/#/subjects/AGZ000857n

Posted May 12, 2015 9:38 AM

by ramberts

I think I saw a few others, but the possible lenses looked like like galaxies in full depth, I'll keep my eye out for others and post the full depth in here if I find some

Posted May 12, 2015 9:47 AM

by Capella05 moderator

As mentioned in one of the related discussions I had with @ramberts several weeks ago - I have also been unable to find any additional / follow up research relating to the candidates posted in this thread. Considering the original source was a letter and not a paper is rather telling.

Also, with 12 years having elapsed and nothing available in the public domain leads me to believe that:

a. The candidates must of been rejected, or;

b. Any research WRT them is hidden behind pay/firewalls, or;

c. They never got followed up on (unlikely).

In either case not a very positive outcome for us wanting more information pertaining to their status.

I have submitted a query to a source that I am unable to access - If I hear anything I will post it.

Posted May 12, 2015 6:52 PM

by ramberts

Here's another one from the article.

Lens Candidate

2004 image

2004

I see Budgieye posted the same concerns I had, the possible lens is really far away. I know the source galaxies bend light, but can the lenses be much further out than the source? I've read an article that the source can be much further away from the lenses, but can it happen vice versa?

http://arxiv.org/abs/1309.2826

http://talk.galaxyzoo.org/?&_ga=1.172416035.1250538510.1430670718#/subjects/AGZ000852x

Posted May 13, 2015 12:16 AM

by Budgieye moderator

A lensed galaxy (the arc) is behind the lensing galaxy, so the lensed galaxy (the arc) is always further away. As a general rule, which is likely to be wrong, it should be at least twice as far away.

My concern with distant lensed galaxies is that measurements are slippery when looking far back when the universe was smaller. It is like trying to measure the size of an insect when you have the ruler between you and the magnifying glass, instead of having the ruler near the insect. The size that you measure will be too big. Distant arcs and the Einstein radius http://talk.galaxyzoo.org/#/boards/BGZ0000005/discussions/DGZ0001f7c

Here is some info on lenses from the forum.

Zooite Guide to Strong Gravitational Lenses http://www.galaxyzooforum.org/index.php?topic=275811.0

Some info from SpaceWarps

The colours of lensing and lensed galaxies http://talk.spacewarps.org/#/boards/BSW0000002/discussions/DSW000044z http://talk.spacewarps.org/#/boards/BSW0000002/discussions/DSW0000302

My Easy Explanation of Strong Gravitational Lenses http://talk.spacewarps.org/#/boards/BSW0000002/discussions/DSW0000302

See the Spotter's guide in SpaceWarps http://spacewarps.org/#/guide

Posted May 13, 2015 6:37 AM

by Budgieye moderator in response to Capella05's comment.

I suppose non of the candidates are top quality.

Posted May 13, 2015 6:44 AM

by ramberts in response to Budgieye's comment.

Ahh, Okay, when I read the article it was talking about the arc or lens as the source galaxy, thought they meant the source as the galaxy that bent the light that formed the lens. I was confused reading it earlier because they were talking about the source having high star formation and the lens galaxy as quiescent and I thought it looked the other way around but now that I know that the source was the actual arc/lens it makes a lot more sense lol. Slowly learning about astronomy...😃 Thanks for the ZOOITE Lensing guides I will read them tomorrow. I do have to say, the old forums are much easier to read/navigate/search/learn about astronomy, hope the new "Talk" makes it more user friendly to look up specific topics, navigate to certain galaxy types etc. I glanced through it the other day and was impressed with how much data is there and how organized everything is.

I looked through the citations of the 2004 article and found none of the galaxies listed through NED or SIMBAD objects included in the articles that had to do with lensing FWIW.

Posted May 13, 2015 7:31 AM

by zutopian in response to Budgieye's comment.

I reply to a post, which had been done some months ago.:
http://talk.galaxyzoo.org/#/subjects/AGZ000825u : Below there is another image of the same galaxy.:

Copy from a new GZ blog post.:

enter image description here

The galaxy that fooled the computer into thinking it had a redshift of 4.25
You can see that there is a bright blue smudge in the top left of the galaxy. When I first saw this, I thought it was a lens. It looks like one, and you can just see a small bit of blue on the other side of the galaxy’s core, suggesting a lens even more. According to the experts in the Zooniverse however, this is probably not a lens, as the galaxy does not look massive enough to lens light. Also, the blue curve is well inside the galaxy, instead of being around the outside. Usually, all the mass of the galaxy is needed to lens an object so the light would appear around the edge. The blue curve is most likely an unusual feature of the galaxy itself, which can explain why the reported redshift is so high.

http://blog.galaxyzoo.org/2015/09/25/galaxy-bars-in-the-summer/

Here is a related GZ Talk discussion about the above statement.:
http://talk.galaxyzoo.org/#/boards/BGZ0000003/discussions/DGZ0001kmc

PS: The above Talk discussion was locked by the moderator Capella05!

Posted September 28, 2015 4:50 AM

by Capella05 moderator in response to zutopian's comment.

@Zutopian : The reason why that thread was locked is because you personally accused me of doing not doing something for a blog that I was not involved with or knew about! I know Mods are meant to have super human skills but really ???!

Posted September 28, 2015 9:49 AM

by zutopian in response to Capella05's comment.

You locked the other topic, but curiously you do a comment here, why you locked it! Since you continued the discussion here, I reply here!
So if you knew, that your comment might appear in a blog post, would you have checked the NED references? Maybe you should have written following in the "GZ Bars Talk" discussion.: "Please don't quote me on this!"
Someone informed me about this topic today! Interestingly, you actually knew the galaxy (472009 is the same galaxy as AGZ000825u) and also the reference paper, because you had done a comment about the same paper in this topic in May! I guess, that you curiously didn't remember!

Posted September 28, 2015 3:15 PM

by zutopian in response to Capella05's comment.

Considering the original source was a letter and not a paper is rather telling.

In the other discussion you did a similar comment.:

Sorry don't want to nit pick but that is a letter not a paper ...

Sorry, but I am not sure, what you mean! Do you critisize, that it is a letter instead of a paper? Well, I think, that it actually doesn't matter, if it is a letter or a paper! The letter had been published in "The Astrophysical Journal Letters", which is a peer-reviewed scientific journal.

Posted September 28, 2015 10:01 PM

by vrooje admin, scientist

I consider Capella05, ElisabethB, and Budgieye (our active moderators here) to each be more expert on lenses than I am. I also think of them as part of the Space Warps science team, not separate from it. If you need evidence of this, check the authorship of the Space Warps papers.

I suggest we stick to the science. Experts don't always agree, and that's part of what makes this source interesting (to me). Sadly scientists often don't publish when a source doesn't turn out to be that interesting, so if someone took a long-slit spectrum of this and it turned out to all be consistent with the same redshift, that could be why there wasn't a follow-up publication. (Alas, there's no SDSS spectrum.)

PS - letters and full-length papers have different roles to play; for the sake of anyone reading along, details on scope for the Astrophysical Journal can be found here.

Posted September 28, 2015 11:08 PM

by zutopian

enter image description here
http://talk.galaxyzoo.org/#/subjects/AGZ00081ea
Hubble Survey: GOODS full-depth

NED Reference:
2004ApJ...600L.155F : "Strong Gravitational Lens Candidates in the GOODS ACS Fields"
Authors.: C. D. Fassnacht, L. A. Moustakas, S. Casertano, H. C. Ferguson, R. A. Lucas, and Y. Park

It is one of the six most promising lens candidates, whose images are presented in above letter (page 3).

Posted September 29, 2015 5:57 PM

by zutopian

enter image description here
http://talk.galaxyzoo.org/#/subjects/AGZ00082xt
Hubble Survey: GOODS full-depth

NED Reference:
2004ApJ...600L.155F : "Strong Gravitational Lens Candidates in the GOODS ACS Fields"
Authors.: C. D. Fassnacht, L. A. Moustakas, S. Casertano, H. C. Ferguson, R. A. Lucas, and Y. Park

It is one of the six most promising lens candidates, whose images are presented in above letter (page 3).

Posted September 29, 2015 9:04 PM

by c_cld

Discovery of a Very Bright and Intrinsically Very Luminous, Strongly Lensed Lyα Emitting Galaxy at z = 2.82 in the BOSS Emission-Line Lens Survey

https://arxiv.org/abs/1702.00989 Rui Marques-Chaves et al., last revised 6 Feb 2017

We report the discovery of a very bright (r = 20.16), highly magnified, and yet intrinsically very luminous Ly{\alpha} emitter (LAE) at z = 2.82. This system comprises four images in the observer plane with a maximum separation of ~ 6" and it is lensed by a z = 0.55 massive early-type galaxy. It was initially identified in the Baryon Oscillation Spectroscopic Survey (BOSS) Emission-Line Lens Survey for GALaxy-Ly{\alpha} EmitteR sYstems (BELLS GALLERY) survey, and follow-up imaging and spectroscopic observations using the Gran Telescopio Canarias (GTC) and William Herschel Telescope (WHT) confirmed the lensing nature of this system. A lens model using a singular isothermal ellipsoid in an external shear field reproduces quite well the main features of the system, yielding an Einstein radius of 2.95" +/- 0.10", and a total magnification factor for the LAE of 8.8 +/- 0.4. This LAE is one of the brightest and most luminous galaxy-galaxy strong lenses known. We present initial imaging and spectroscopy showing the basic physical and morphological properties of this lensed system.

enter image description here

SDSS J142954.80+120235.6 1237662528993886732

1237662528993886732 LRG & quad A,B,C,D

SpecObjID = 6150824552022544384

Posted February 7, 2017 1:09 PM