Space Warps Talk

Processing candidate ASW0004dv8

  • c_cld by c_cld

    ASW0004dv8

    ASW0004dv8

    After nailing down the coords of the candidate which is CFHTLS1166_061401 ra=02 24 09.541 dec=-10 58 07.72 i've done some image processing with the bands by Aladin tool.
    I used the technique of subtracting i-band from g-band to enhance the lensed feature: below is what seems convincing:

    ASW0004dv8

    Its circle radius is ~2.8 arcsec.

    Is there some volunteer to model it yielding some estimates of lens and source redshifts? Thanks

    Posted

  • JasonJason by JasonJason

    Model of ASW0004dv8

    Model results for ASW0004dv8: Plausible


    Posted

  • Tom_Collett by Tom_Collett scientist in response to C_cld's comment.

    Nice idea to subtract g from i! It's one of the old ways we I tried to find lenses before spacewarps, it works pretty well because lenses are red and sources are blue.

    Unfortunately you can't learn the redshifts from the Einstein radius or modelling the system, because we don't know the mass of the system. We have to take a spectrum of the galaxy and source to learn their redshifts (although we can make a good guess based on their colors). If we knew the redshifts we could learn about the mass, but 2.8 arcseconds for an Einstein radius is definitely a pretty chunky galaxy - indeed this is actually a group scale lens. You can tell it's a group because the image has loads of other galaxies of similar color (in this case yellow) to the lens galaxy. In fact the image has so many that I suspect it's more of a low mass cluster than a group.

    Posted

  • c_cld by c_cld

    quick model http://mite.physik.uzh.ch/data/004506 to be revised

    Posted

  • c_cld by c_cld

    revision with a point mass http://mite.physik.uzh.ch/data/4536

    Posted