NOAO >   Observing Info >   Approved Programs >   2009B-0552

# Proposal Information for 2009B-0552

PI: Ian Dell'Antonio, Brown University, ian@het.brown.edu
Address: Physics Department, Box 1843, Physics Department, Brown University, Providence, Rhode Island 02912, USA

CoI: Richard Cook, Brown University, Physics Department
CoI: Paul Huwe, Brown University, Physics Department
CoI: Van Anh Dao, Brown University, Physics Department

Title: OPTIC Observations of Clusters: Testing PSF-Induced Biases in OT Guided Weak Lensing Analyses

Abstract: Orthogonal transfer (OT) array detectors are increasingly being adopted for existing, in-construction and proposed wide-field imaging cameras. The smaller PSF possible with OT devices can be extremely valuable to both strong and weak gravitational lensing studies. However, the OT fast guiding only corrects the PSF locally, and it introduces spatial variability in the PSF that can bias weak lensing shear measures. Therefore, local OT guiding might be \it less efficient for weak lensing than unguided or coherently guided observations. We propose to use Optic to observe three clusters of galaxies in a way that simultaneously" produces an OT and non-OT guided image of the cluster galaxies. We will then use shapes of the background galaxies to produce weak lensing shear maps for the two images to test the competing effects of image quality improvement and PSF distortion on the final map. This experiment is particularly timely as a test of the potential of the planned OT guide modes of the ODI camera.

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 NOAO >   Observing Info >   Approved Programs >   2009B-0552