Space Warps Talk

Modelling the CFHTLS-SW candidates

by psaha scientist

The list of candidates discovered by the Spacewarps community is now out: http://arxiv.org/abs/1504.05587

And so is the new improved SpaghettiLens http://labs.spacewarps.org/spaghetti/ thanks to @rafael_kueng who single-handedly vanquished the computer, the network and all other evil things around!

Posted April 24, 2015 6:49 AM
by Capella05 moderator

Edited to add: I am so excited we are modelling again 😃 😃 😃

As with all our modelling attempts can you:
- Only have a single model in a post.
- List the parent of the model (if applicable)
- The ID of the model you have just generated
- The changes you have made to the model
- The results of your changes.
- Thoughts for improvement.
For Example:
- SW ID - The Spacewarps ID of the candidate
- Parent - 4516
- Revised Model - 4568
- Action - Moved the minima to the NE of the galaxy and added a mass point.
- Result - The arc is more clearly defined from 7 to 11:30, not too happy about the predicted counter image at 2:45
- Thoughts - Perhaps a cleaner mass distribution?
And a template - amend where necessary! Just copy and paste 😃
```
 - ***SW ID*** -  insert text here
 - ***Parent*** -  insert text here
 - ***Revised Model*** - insert text here
 - ***Action*** -  insert text here
 - ***Result*** - insert text here
 - ***Thoughts*** -  insert text here

.

 <IMG SRC="http://labs.spacewarps.org/media/spaghetti/JQ/A3OBCT52/img3_ipol.png" WIDTH="220">
 <IMG SRC="http://labs.spacewarps.org/media/spaghetti/JQ/A3OBCT52/img1.png" WIDTH="220">
 <IMG SRC="http://labs.spacewarps.org/media/spaghetti/JQ/A3OBCT52/img2.png" WIDTH="220">
 <IMG SRC="http://labs.spacewarps.org/media/spaghetti/JQ/A3OBCT52/input.png" WIDTH="220">
```
Posted April 24, 2015 4:09 PM
by Capella05 moderator
- SW ID - ASW0004wgd #SW34
- Parent - n/a
- Revised Model - JQA3OBCT52
- Action - n/a
- Result - nice mass distribution and contour lines
- Thoughts - make the synthetic image resemble the visible arc more.
.

Posted April 24, 2015 5:02 PM
by Capella05 moderator
- SW ID - ASW0002p8y #SW29
- Parent - n/a
- Revised Model - 3BJQ2QZN65
- Action - n/a
- Result - Not very convincing at the moment. The arc (in the image) seems to contour the middle galaxy in the group, discounting the other two. Sheer guess work at this point on where to place the points
- Thoughts - all welcome!
.

Posted April 24, 2015 6:49 PM
by Capella05 moderator
- SW ID - ASW0008qsm #SW28
- Parent - n/a
- Revised Model - EYVRGDM2OE
- Action - n/a
- Result - Not convincing.
- Thoughts - This one is proving to be a bugger to model, after 15+ attempts I am still not happy with results. The contour maps and mass distribution are always messy. I discounted the larger blue mass as being the counter image, and went for the smaller one, closer to the lens galaxy.
.

Posted April 25, 2015 8:15 AM
by Capella05 moderator
- SW ID - ASW00070vl #SW52
- Parent - n/a
- Revised Model - M36RZR4OC4
- Action - n/a
- Result - initial model - to be refined.
- Thoughts - A starter - to be built upon.
.

Posted April 25, 2015 8:49 AM
by c_cld
- SW ID - ASW0007sez #SW53
- Parent - n/a
- Revised Model - CCZG2QBCV3
- Action - n/a
- Result - looks good
- Thoughts - ?
.

Posted April 25, 2015 8:55 AM
by c_cld
- SW ID - ASW00021r0 #SW30
- Parent - n/a
- Revised Model - Y4NEUEI45Y
- Action - n/a
- Result - passable
- Thoughts - increase north arc?
.

Posted April 25, 2015 9:05 AM
by Capella05 moderator
- SW ID - ASW0004m3x #SW20
- Parent - n/a
- Revised Model - HOHZKGVFHT
- Action - n/a
- Result - The Synthetic image looks nice, but the rest goes downhill...
- Thoughts - Mass distribution is really ugly - needs improvement. Perhaps another mass point at 3 on the neighbouring galaxy?
.

Posted April 25, 2015 10:05 AM
by Capella05 moderator
- SW ID - ASW00021r0 #SW30
- Parent - Y4NEUEI45Y from @C_cld
- Revised Model - 2CZ5QU37NJ
- Action - Inserted a saddle point.
- Result - The arc is more clearly defined and there is definition to to the north. The contour plot map has degraded.
- Thoughts - need to create a more defined gap at 2.
.

Posted April 25, 2015 10:55 AM
by ElisabethB moderator
- SW ID - ASW0008xbu
- Parent - n/a
- Revised Model - BFXRMIQEAT
- Action - n/a
- Result - contour plot and mass distribution look clean. Not sure about the synthetic image.
- Thoughts - needs more work
.

Posted April 25, 2015 1:41 PM
by Capella05 moderator
- SW ID - ASW0006mea #SW3
- Parent - n/a
- Revised Model - XZDGINWFYY
- Action - n/a
- Result - Actually looks quite good!
- Thoughts - Deciding where to place the counter image is guess work, due to the bright star at 5. Starter model to work upon.
.

Posted April 25, 2015 3:34 PM
by Capella05 moderator
- SW ID - ASW00008a0 #SW49
- Parent - n/a
- Revised Model - 5WB7AO4WUY
- Action - n/a
- Result - Look okay - needs tweaking.
- Thoughts - Even under magnification I am unable to pinpoint the counter image - ideas?
.

Posted April 25, 2015 5:27 PM
by ElisabethB moderator
- SW ID - ASW0008qsm
- Parent - n/a
- Revised Model - M6IXERVPB4
- Action - n/a
- Result - Synthetic view: too much of a ring ? Contour plot could be better. Mass distribution reasonably clean.
.

Posted April 25, 2015 5:48 PM
by Capella05 moderator
- SW ID - ASW0007hu2 #SW17
- Parent - n/a
- Revised Model - D4UQI6M3ZU
- Action - n/a
- Result - The contour map and mass distribution look really odd. Not very convincing at this point.
- Thoughts - Will revisit at some point, and remodel
.

Posted April 25, 2015 6:22 PM
by ElisabethB moderator in response to Capella05's comment.

Contour plot looks reminds me of a one eyed Homer Simpson ! 😄

Posted April 25, 2015 6:27 PM
by ElisabethB moderator in response to Capella05's comment.
- SW ID - ASW000096t
- Parent - n/a
- Revised Model - ZHRZSBEAN5
- Action - added lots of point masses since this looks like a cluster.
- Result - Synthetic image : too much of a ring. Contour plot : not that great. Mass distribution : reasonable.
- Thoughts - definitely needs improvement.
.

Posted April 25, 2015 6:33 PM
by Capella05 moderator in response to ElisabethB's comment.

Lol - didn't see that until you pointed it out!

Posted April 25, 2015 6:55 PM
by Capella05 moderator in response to ElisabethB's comment.
- SW ID - ASW0000g95
- Parent - n/a
- Revised Model - XF5TQSXZDQ
- Action - n/a
- Result -
- Thoughts - a starter to work upon.
.

Posted April 25, 2015 7:09 PM
by ElisabethB moderator
- SW ID - ASW00085cp
- Parent - n/a
- Revised Model - 6IU7DLN5GK
- Action - n/a
- Result - very basic model
- Thoughts - contour plot very basic, mass distribution fairly clean. lots of improvement possible ! 😉
.

Posted April 25, 2015 7:25 PM
by Capella05 moderator
- SW ID - ASW00021r0 #SW30
- Parent - 2CZ5QU37NJ from @Capella05
- Revised Model - EPEDEGOBNV
- Action - Cleaned up the Spaghetti, adjusted the saddlepoint by moving it slightly toward the northern arc. Repositioned the right minima point. Moved the initial point slightly towards the maxima.
- Result - Looking better!
- Thoughts - Contour map and mass distribution have been improved. The arc is plausible.
.

Posted April 26, 2015 10:51 AM
by Capella05 moderator
- SW ID - ASW0004m3x #SW20
- Parent - HOHZKGVFHT from @Capella05
- Revised Model - VTGDU6KOBA
- Action - Inserted a second mass point to the right. Adjusted the Spaghetti.
- Result - Not much change visible.
- Thoughts - Mass distribution and contour plot map needs to be improved. Suggest tweaking the position of the saddlepoint next.
.

Posted April 26, 2015 11:14 AM
by Capella05 moderator
- SW ID - ASW0004m3x #SW20
- Parent - VTGDU6KOBA from @Capella05
- Revised Model - I2AODKYMKN
- Action - Adjusted the left mass point to place it more cleanly over the satellite galaxy. Also repositioned the maxima, initial minima and saddlepoint.
- Result - starting to look a bit more plausible!
- Thoughts -
.

Posted April 26, 2015 12:15 PM
by Capella05 moderator
- SW ID - ASW0004m3x #SW20
- Parent - I2AODKYMKN from @Capella05
- Revised Model - PGTZG3KCTV
- Action - tweaked the size of the left mass point. Adjusted the lower right minima.
- Result - Plausible.
- Thoughts - Last attempt on this candidate - running out of ideas. Els, Claude?
.

Posted April 26, 2015 12:49 PM
by Capella05 moderator
- SW ID - ASW000096t #SW35
- Parent - ZHRZSBEAN5 from @ElisabethB
- Revised Model - 7IPP7LWVOF
- Action - Removed the second saddlepoint, and adjusted the mass point to the lower right.Pumped up the pixel radius to 10.
- Result - Mass distribution has degraded.
- Thoughts - needs a few tweaks.
.

Posted April 26, 2015 1:23 PM
by Capella05 moderator
- SW ID - ASW0009cox #SW37
- Parent - n/a
- Revised Model - KCX5ZKZCYU
- Action - n/a
- Result - Convincing
- Thoughts - Needs a few tweaks - but looks good!
.

Posted April 26, 2015 2:44 PM
by ElisabethB moderator

i was also working on this one. 😃
- SW ID - ASW0009cox SW37
- Parent - n/a
- Revised Model - CLH5R3M5SP
- Action - n/a
- Result - similar to Capella05's model
- Thoughts - needs some work
  .
Posted April 26, 2015 3:50 PM
by Capella05 moderator in response to ElisabethB's comment.

I love the contour lines on your one - way better than mine!

Posted April 26, 2015 3:55 PM
by ElisabethB moderator
- SW ID - ASW0009cox
- Parent - 67GLBVRIEU from @ElisabethB
- Revised Model - 5P5PSM2PUJ
- Action - moved the minima in a bit and the maximum a bit more to the center
- Result - cleaner contour plot and mass distribution
- Thoughts - not sure about the synthetic image
.

Posted April 26, 2015 4:11 PM
by ElisabethB moderator
- SW ID - ASW00008a0
- Parent - n/a
- Revised Model - ZQTCPBN3ZE
- Action - n/a
- Result - reasonably clean mass distribution and contours
- Thoughts - first attempt, definitely needs some tweaking
.

Posted April 26, 2015 7:03 PM
by c_cld
- SW ID - ASW0008qsm #SW28
- Parent - EYVRGDM2OE from @Capella05 (incorrect saddle)
- Revised Model - TQKS2E5S7H
- Action - the image nearer to the galaxy is a single saddle point, and the image further away is a minimum.
- Result - fairly good
- Thoughts - difficult to model a #double as the closest image to the deflector is smearing as small arc.
.

Posted April 27, 2015 8:47 AM
by c_cld
- SW ID - ASW0004m3x #SW20
- Parent - PGTZG3KCTV from @Capella05
- Revised Model - QZROE23AUH
- Action - simplified spaghetti, putting images separation down to standard
- Result - passable
- Thoughts - image very weakly curved?
.

Posted April 27, 2015 9:11 AM
by c_cld
- SW ID - ASW0006a07 #SW51
- Parent - 6437 from @c_cld
- Revised Model - 13589
- Action - tuning triple, z_spec DR7 0.6
- Result - convincing
- Thoughts - to duplicate in new SL release 😃
.

Posted April 27, 2015 9:26 AM
by ElisabethB moderator

Btw, really nice models Claude. Very clean ! 😄
- SW ID - ASW0004xjk
- Parent - n/a
- Revised Model - P5W2HUVWX3
- Action - n/a
- Result - Syntethic image : iffy. Reasonably clean Contours and Mass distribution.
- Thoughts - Not sure about this one. I'm trying to model the arc around the little red galaxy, but the bigger yellow one seems like a more likely candidate. But that gives really really crappy results.
.

Posted April 27, 2015 6:10 PM
by c_cld
- SW ID - ASW00024id #SW44
- Parent - n/a but in previous SL release
- Revised Model - EL3RTBLAWB
- Action - guess 1st saddle different from http://mite.physik.uzh.ch/data/013557
- Result - mass map smooth elliptic, synthetic lack of circle brightness mainly for SE spot
- Thoughts - spots diagonals 3.4" x 4.8" more elliptic than circular: need shear or reject as imposter?
.

similar http://labs.spacewarps.org/spaghetti/model/TSKKYHD3CB

Posted April 28, 2015 3:51 PM
by c_cld
- SW ID - #SW48 ASW00007ls ASW000066w
- Parent - n/a
- Revised Model - KEDFRTYJXH
- Action - n/a
- Result - good
- Thoughts - ?
.

Posted April 29, 2015 12:25 PM
by ElisabethB moderator
- SW ID - ASW0007sez
- Parent - n/a
- Revised Model - SI4ELBAKL2
- Action - n/a
- Result - 1st try
- Thoughts - not too bad
.

Posted April 29, 2015 5:12 PM
by c_cld in response to ElisabethB's comment.

ASW0007sez

@Els I don't know how you succeed to load this image, because I already modeled it at http://labs.spacewarps.org/spaghetti/model/CCZG2QBCV3: when I try to start a model from an ASW id, I got an error from Spaghettilens "OUuups, that should not pappen(sic).. Please inform Rafa what you did!"

#SW53: Anyway I suggest that you look at the object in "Tools" http://tools.zooniverse.org/#/dashboards/spacewarp/5541168ea3514c519500025d or in Aladin filters to find a very different case of your model.

There is not need to put 2 saddles and 2 minima, and I think your saddle is misplaced as it should be the right fainter counter image of the left brightest blue blob/arc . (I reviewed Rafa's paper on the mistakes we made for sims).

Modeling could be a demanding and painstaking work but it's worth to progress on this sample of candidates 😃

Posted April 29, 2015 6:07 PM
by Capella05 moderator

@Els I don't know how you succeed to load this image, because I already modeled it at http://labs.spacewarps.org/spaghetti/model/CCZG2QBCV3: when I try to start a model from an ASW id, I got an error from Spaghettilens "OUuups, that should not pappen(sic).. Please inform Rafa what you did!"

That has already been raised on Github (along with several other issues), go to the Spaghettilens repository to see Rafi's responses.

There are no correct or incorrect models - each of us can model the candidates as we see fit, and make changes. Sometimes the changes will improve the model and sometimes it won't 😃 Sometimes we might feel like trying something different, that will result in a horrible model. We may choose to post it, to show the others what to avoid.

Can we please try to avoid negative language like 'incorrect' 'wrong' 'do this instead' - and rather try positive enforcement like 'If you tried moving the saddlepoint to x, you might get a better y'.

The only reason I am asking is that we will be training other modellers, and I do not want to scare them off by any perceived negativity, or for them to think that they have no freedom in how they choose to model. 😃

This is not geared towards anyone in particular, but we have to start thinking about the future and how to attract more modellers 😃

Posted April 29, 2015 7:51 PM
by psaha scientist in response to ElisabethB's comment.

This system is a difficult one, but the model looks definitely on the right track!

Interpreting the model, we have a main lensing galaxy and a perturbing galaxy; the perturbing galaxy is probably more massive than the main lensing galaxy, but still, it does not dominate because it's not as close (in projection) to the source. The perturbing galaxy is approximated by a point mass, which is not ideal, but the best we can do with the current capabilities SpaghettiLens.

In such situations you expect the arrival-time contours, and by extension the arcs, to be squashed away from the perturber. The model shows just that, which is good.

Posted April 30, 2015 2:46 PM
by psaha scientist in response to C_cld's comment.

Maybe a four-image morphology (analogous to EL3RTBLAWB) could be tried?

Posted April 30, 2015 2:52 PM
by Capella05 moderator
- SW ID - ASW00021r0 #SW30
- Parent - n/a
- Revised Model - UHUIOLRHVW
- Action - n/a
- Result - Mass distribution and contour map is good. The synthetic image is plausible given my comments below.
- Thoughts - I have gone in a rather radical direction from my previous models for this candidate. I do not think the lower right brighter blue 'arc' is connected, but rather foreground star/s (having said that - there could well be an arc obscured behind!). Next I am going to try inserting a second saddle point to see if it will improve or degrade the model.
.

Posted May 2, 2015 5:05 PM
by Capella05 moderator
- SW ID - ASW00021r0 #SW30
- Parent - UHUIOLRHVW
- Revised Model - SYTNGELH3Q
- Action - Move the initial minima and created a saddle point. Moved the initial saddle point closer to the lens galaxy.
- Result - Hmmmm - okay, I guess. Previous attempt was better.
- Thoughts - I am focusing on modelling the northern arc, rather than the deeper blue 'arc' in the 3 o'clock position.
.

Posted May 2, 2015 5:29 PM
by Capella05 moderator
- SW ID - ASW0007pga #SW55
- Parent - n/a
- Revised Model - VHV6RQYYKZ
- Action - n/a
- Result - hmmmm. Needs a bit of work.
- Thoughts - A hard one - edge on's have always been difficult to model with SpaghettiLens. Not that convinced with this one.
.

Posted May 9, 2015 5:49 PM
by c_cld
- SW ID - #SW18 ASW0001ld7
- Parent - n/a
- Revised Model - L5TWWXPEJV
- Action - n/a
- Result - good
- Thoughts - ?
  .
Posted May 11, 2015 8:49 AM
by c_cld
- SW ID - #SW26 ASW0006jh5
- Parent - n/a
- Revised Model - GSI5A6JUYX
- Action - n/a
- Result - good
- Thoughts - ?
  .
Posted May 11, 2015 9:29 AM
by c_cld
- SW ID - #SW10 ASW0002qtn
- Parent - n/a
- Revised Model - FFIENOES3L
- Action - n/a
- Result - good
- Thoughts - mass not smooth enough
  .
Posted May 11, 2015 11:00 AM
by c_cld
- SW ID - ASW00099ed (in SW II last version / discoveries)
- Parent - n/a
- Revised Model - HISGRAIZL2
- Action - n/a
- Result - good
- Thoughts - ?
  .
Posted May 11, 2015 2:12 PM
by c_cld in response to Capella05's comment.
- SW ID - ASW0008qsm #SW28
- Parent - EYVRGDM2OE from @Capella05
- Revised Model - 2SU75GA4XN
- Action - kept one saddle and one minimum only and shifted saddle
- Result - after many good mass maps but arc, I choosed a degraded mass map but a #double
- Thoughts - always difficult to model a double (outcome is often an arc or a ring and rarer a cross)
.

Posted May 12, 2015 7:21 PM
by psaha scientist in response to C_cld's comment.
- SW ID - ASW0008qsm #SW29
- Parent - 2SU75GA4XN by @C_cld
- Revised Model - TOFS7JNGEK
- Action - Tried another configuration
- Result - Plausible
- Thoughts - Arc near the galaxy could be saddle+minimum-saddle.
.

Posted May 20, 2015 9:42 AM
by psaha scientist
- SW ID - ASW00096rm SW42
- Parent - n/a
- Revised Model - GVYUDXDXLB
- Action -
- Result - Not very satisfactory
- Thoughts - Not a lens?
Posted June 11, 2015 1:22 PM

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