28 September 2009
Elinor Medezinski (Tel Aviv)
'The Full Strength of Cluster Lensing'
I show how to isolate background galaxy populations for a proper
weak-lensing measurements. Published work has suffered significant
contamination by cluster members which dilute the central weak-lensing
signal, leading to underestimated mass profiles. Accurate and reliable
cluster mass and light profiles are then constructed for several well
known clusters with deep multi-color Subaru data and HST/ACS
strong-lensing, well fitted by surprisingly high-concentration NFW
profiles and where M/L peaks at ~0.2 R_vir.
For the first time we demonstrate that the distant dropout population
has a higher weak-lensing signal than the blue and red populations of
background galaxies, from which we derive the lensing
distance-redshift relation for A370, ZwCl0024+17 and RXJ1347-11. Here
the depth of the background populations are estimated with reference
to the COSMOS 30-band survey of Ilbert et al, for which we can clarify
photometric redshift ambiguity.