Full strength of (weak) Cluster lensing

1. Full strength of (weak) Cluster lensing Elinor Medezinski Tel Aviv University Advisors: Tom Broadhurst, Yoel Rephaeli Collaborators: Keiichi Umetsu, Narciso Benitez, Dan Coe, Holland Ford, Masamune Oguri Medezinski et al. 2007, Broadhurst et al. 2008, Medezinski et al. 2009, Medezinski et al. 2010 (in prep)

2. New approach - Color-Color • B,R,z’ for A370 • V,R,z’ for RXJ1347 • g’,r’,i’ for A1703 (Medezinski et al. 2009) • Galaxy number density map • 4 Density peaks – different galaxy populations A370

3. Average radius in Color-Color space • Color code = distance from cluster center • Blue = low mean radius – cluster galaxies A370

4. Sample selection in Color-Color • Red – background • Blue – background • Green– cluster +~background • Pink – foreground +background A370

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

6. Dilution in other work • Oguri et al. 2009 • Diluted by a factor of ~2 in the center • Leads to underestimated Einstein radius • Leads to underestimated Cvir A1703

7. Broadhurst et al. 2008 • gT-profiles agree • NFW fits give high concentrations (Cvir=rvir/rs) than expected by ΛCDM N-body simulations • Use magnification to check consistency of gT results

8. NFW parameters • Cvir-Mvir 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 • A1689 • A1703 • A370 • RXJ1347-11 • 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)

10. Weak lensing strength vs. redshifttest of cosmology using WL distortions(Medezinski et al. 2010 in prep) In the weak limit, Lensing distance vs. redshift:

11. Weak lensing samples • Select background galaxy samples –”red”, “blue”, “green” and “dropouts” and measure their lensing profile • Red – background • Blue – background • Green–background • Pink – background (high-z dropouts) A370

12. COSMOS Redshifts 30-band wide field (2 sq. deg.) survey (Capak et al. 2007) Photometric redshifts catalog (Ilbert et al. 2009) mean redshift in color-color space Same selection samples

13. Faint Bright Results: • gT amplitude vs. redshift overlaid on the lensing distance – redshift curves A370 ZwCl0024-17 RXJ1347-11

14. 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 constrain the lensing distance – redshift relation. Future work: • Obtain photo-z’s using more colors for consistency checks. • Extend to other clusters (CL0024 submitted Umetsu et al. 2009, MACS sample) using existing Subaru. • Combine w/ strong-lensing from HST/ACS (Zitrin et al. 2009) – Hubble MCT proposal accepted!! – 25 clusters with 525 orbits. • Constrain mass distribution by combining X-ray and SZ from Chandra and Amiba (Amiba paper - Umetsu et al. 2009).