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Some Initial Results on Abell611. MSSG, JCY Followup Presentation to David, Paul and Klaus For DOE WL proposal Th Dec 13, 2007. Images of A611. R_2. G_2. U_2. Working mostly with the WCS-matching improved images in 3 bands prepared by Paul. Cut Images. R_2. G_2. U_2.
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Some Initial Results on Abell611 MSSG, JCY Followup Presentation to David, Paul and Klaus For DOE WL proposal Th Dec 13, 2007
Images of A611 R_2 G_2 U_2 Working mostly with the WCS-matching improved images in 3 bands prepared by Paul
Cut Images R_2 G_2 U_2 As shapelets takes several hours to fully process each image, we decided to cut out the central 4100x4100 pixel to speed up process (about 8’x8’); these still take about 4*2 hours each to process (excluding crashes etc.) (No such cutting needed for imcat, longest step in process is about 15 min)
Color Bands Image Matching • Ideally cut on color to try to select galaxies behind cluster • Images not perfectly aligned yet apparently, so can’t use this cut, should be quite effective when we have it in hand • Left: very few color-matched objects; Right: offset in G- and R- bands
Shapelets-Imcat Match • Conversely, a good match is seen in object positions in shapelets vs. imcat • Left: matched objects (R-band); Right: zoom into BCG
2D Sextractor Ellipticity Map, Stars (before deconvolution) Shows the size and direction of the psf, which appears roughly continuous R-band
Radial Profile; Imcat – Emode – R-band 2000 pixels =~ 8’ (0.242” / pixel)
Radial Profile; Shapelets – Emode – G-band (gamma and gksb cuts of 2)
Future work • Try color cut, once objects are aligned; look at u-band profiles. • Figure out optimal magnitude / size / other cuts to select foreground galaxies • See how changing center point of cluster affects profile • Try new sky.pro vs. /meanback option for background estimation in shapelets • Eliminate bad stars from psf estimation • Make 2D grid ellipticity plots for all bands, before and after psf deconvolution • Have created a *lot* of files, need to organize these so we can easily refer to them later
2D Sextractor Ellipticity Map, Galaxies (before deconvolution) Cluster center is at about (2083, 2009) in these coordinates R-band
2D Sextractor Ellipticity Map, (before deconvolution) G-band
2D Sextractor Ellipticity Map, -- Smoothed (before deconvolution) Some indication of cluster center seen here G-band
R-band: gamma and gksb cuts of 0.7Shapelets results; E and B