Date:
Tue, 16/02/201012:30-13:30
Location:
Kaplun Bldg, seminar room, 2nd floor
THE FULL STRENGTH OF CLUSTER LENSING
I show how to isolate background galaxy populations for a proper weak-lensing measurement. 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 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 depths 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.
I show how to isolate background galaxy populations for a proper weak-lensing measurement. 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 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 depths 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.