Using Weak Lensing Dilution to Improve Measurements of

Using “Weak Lensing Dilution” to Improve Measurements of Luminous and Dark Matter in A 1689 Medezinski et al. 2007 Elinor Medezinski Advisors: Tom Broadhurst, Yoel Rephaeli Collaborators: Keiichi Umetsu, Narciso Benitez, Dan Coe, Holland Ford, Nobuo Arimoto, Xu Kong Technion, July 25 th 2007

Gravitational Lensing The lens equation Image Source Lens Observer

Weak-lensing A 1689 z = 0. 183 n Subaru n Suprime. Cam 34’x 27’ Strong-lensing HST ACS 3. 3’x 3. 3’ 30’ Chandra ACIS n Arcs

Weak Lensing Shear n Tangential shear – measured relative to cluster center

Color-magnitude Red n E/SO sequence galaxies Blue Cluster sequence

Color-magnitude n n E/SO sequence galaxies Three galaxy samples n n n Red background Blue - faint background Green – cluster +background Red Blue

Setting limits n Distortion reduces closer to the cluster sequence

n Distortion of bright cluster galaxies, i<21. 5 mag – zero signal g. T=0. 0043

Weak Lensing Distortion n n Background Distortion declines gradually with radius Green – distortion diluted by unlensed cluster members The “Dilution” effect

Weak Lensing Distortion n n ACS (r<2’) +Subaru Saw-tooth pattern of strong lensing Max – tangential critical curve, ~47’’ Min – radial critical curve, ~17’’

Fraction = Cluster Membership n n Dilution to measure cluster membership Correct for red/blue relative depths

Cluster Luminosity Profile n n n Cluster luminosity – “g-weighted” flux to get cluster flux Flux Luminosity Linear fit

Mass to Light Ratio n n High M/L ~ 480 Agrees with M/L inside 2’ from Broadhurst et al. 2005 a Mass estimates from lensing M/M* n Mass profile from Broadhurst et al. 2005 a, b M*/L vs. color from Bell et al. 2003

Cluster Luminosity Function n Flat, no upturn

Distortion profile fits n n NFW profile Best fit: High concentration

Summary n n n Have determined light profile, color profile and radial luminosity functions of A 1689 reliably, with no need to resolve the cluster sequence based on color. Constructed flat luminosity function, with no need for far-field counts for background subtraction Deduced high NFW concentration Future work: n n n Obtain photo-z’s using more colors for consistency checks. Extend to other clusters (CL 0024, A 370, A 1703…) using existing Subaru and ACS data. Constrain mass distribution by combining X-ray data and SZ effect.

Next Cluster – A 1703