Full strength of (weak) Cluster lensing Advisors: Tom Broadhurst, Yoel Rephaeli Collaborators: Keiichi Umetsu, Narciso Benitez, Dan Coe, Holland Ford, Masamune Oguri, Andy Taylor Granada CLASH team meeting, Sep 21 st, 2010 Medezinski et al. 2007, Medezinski et al. 2010a, Medezinski et al. 2010b (submitted) Elinor Medezinski Tel Aviv University

2 A370 (z=0.375) The most massive cluster known, ~3*10 15 M o

3 Subaru data reduction For each filter of each cluster use Subaru pipeline: –Renaming –Overscan and bias subtraction –Making flat frames –Flat fielding –Distortion and atmospheric dispersion correction –PSF size measurement –PSF size equalization –Sky subtraction –Masking out AG probe –Masking out bad regions –Alignment –Co-adding Derive zeropoints Catalog making: SExtractor (ColorPro) + imcat shapes (KSB)

4 Subaru Cluster Dataset Status 8.5 clusters done

5 Weak Lensing Dilution Oguri et al Diluted by a factor of ~2 in the center Leads to underestimated Einstein radius Leads to underestimated C vir A1703

6 Weak lensing profiles A370 g T profiles – rising background signal ~zero for green – diluted by unlensed cluster members Cluster membership – almost ~100% for entire radius range, →green sample is comprised mostly of cluster. “Dilution” method Red – background Blue – background Green – cluster +~background Pink – foreground +background Weak lensing measured using IMCAT (Umetsu & Broadhurst 2008, Umetsu, Medezinski et al. 2010)

7 Setting limits Distortion reduces closer to the cluster sequence Red sample lower limitBlue sample upper limit

8 NFW parameters C vir -M vir comparison with other studies and ΛCDM 4σ discrepancy with ΛCDM, even considering orientation and selection bias (Hennawi et al 2007, Oguri & Blanford et al. 2009)

9 Luminosity & M/L profiles Cluster luminosity – “g-weighted” flux to get cluster flux Flux  Luminosity Linear fit M/L goes down in the outskirts – morphology-density related effect (Dressler 1980) A1689 *A1703  A370 ♦RXJ

10 Cluster Luminosity Function – A1689 Flat faint-end, no upturn

11 Weak lensing strength vs. redshift cosmological tool using WL distortions (Medezinski et al. 2010b, submitted) In the weak limit, Lensing distance vs. redshift:

12 Weak lensing samples Select background galaxy samples – “orange”, “green” ”red”, “blue”, and “dropouts” and measure their lensing profile A370 Grey – foreground Orange – background Green – background Red – background Blue – background Pink – background (high-z dropouts)

13 Fit background WL distortion profile with power law: Find amplitude a i for other samples, with same power law Bright Faint Grey – foreground Orange – background Green – background Red – background Blue – background Pink – background (high-z dropouts)

14 COSMOS Redshifts 30-band wide field (2 sq. deg.) survey (Capak et al. 2007) Photometric redshifts catalog (Ilbert et al. 2009) Same selection samples mean redshift in color- color space Grey – foreground Orange – background Green – background Red – background Blue – background Pink – background (high-z dropouts)

15 Samples photo-z distributions Separated redshift bins Selection in different field Grey – foreground Orange – background Green – background Red – background Blue – background Pink – background (high-z dropouts)

16 COSMOS vs. GOODS General agreement Low-z peak mostly erroneous Examine low-z contamination vs. color limit to make cuts

17 WL and redshift vs. magnitude Red increases as expected Blue decreases – sign of shape underestimatio n at faint mags D ds /D s agrees – cannot determine redshifts accurately beyond z’~25 Grey – foreground Orange – background Green – background Red – background Blue – background Pink – background (high-z dropouts)

18 g T amplitude vs. redshift overlaid on the lensing distance – redshift curves Using 25 A370’s - Δw≈0.6 RXJ A370 ZwCl Faint BrightResults:

19 Summary Developed new scheme to resolve cluster/foreground/background selected in color-color space and better determine weak lensing profiles. Determined light profiles & radial luminosity functions of A1689, A1703, A370, RXJ1347 reliably, with no need to resolve the cluster sequence based on color. Found flat luminosity function, with no need for far-field counts for background subtraction. Constructed M/L profiles to the virial radius, showing physical behavior of DM to light distributions, dropping to the center of cluster, and also dropping to the outskirts. Deduced high NFW concentrations, contradicting ΛCDM simulation expectation values. Use weak lensing distortions to determine the lensing distance – redshift relation, and thereby constraining cosmological parameters – Δw≈0.6. Recent & Future work: Obtain photo-z’s using more colors for consistency checks. Determine methods uncertainties due to shapes, redshifts, sample selection etc w/ simulations. Combine w/ strong-lensing from MCT/CLASH. Constrain mass distribution by combining X-ray (Lemze et al. 2008) and SZ (Umetsu et al. 2009).