0 Assigned ID: 1028 ----- Attempting Submission 1 (Thu Feb 21 02:32:27 GMT 2013) ----- HST Phase I Proposal 1028 (MarusaBradac_FF.apt) successfully submitted. ----- Attempting Submission 2 (Fri Mar 01 21:37:44 GMT 2013) ----- Cluster-scale gravitational lenses act as cosmic telescopes, enabling the study of intrinsically lower luminosity galaxies, which would otherwise be impossible. However, in order to use these cosmic telescopes we also need a robustly derived magnification maps and error analyses. These are essential to understand the systematic errors present in such investigations. While the STScI special call for proposals to get magnification information will provide the first-order maps, this proposal will add (i) HST ultra deep Frontier Field data (not available for the call), (ii) Keck and VLT spectroscopy, (iii) improved weak lensing treatment, and (iv) flexion analysis to produce a factor of 2 improvement in the magnification estimates. This will be a crucial legacy complement to the existing efforts to provide magnification maps for these clusters and we plan to release the improved maps to the community. By reaching fainter luminosities, with this proposal we will study the faint-end slope of the luminosity function for the highest redshift galaxies. This will enable the study of their contribution to the bulk of ionizing photons necessary to drive reionization. Furthermore we will study the role that these galaxies play in the galaxy formation models through the measurement of their sizes. Both tasks are made possible by the powers of cosmic telescopes and our proven techniques for accurate quantification of magnification. COSMOLOGY Default Medium false false false false false SUPPORTED