Preliminary Optical Design for a 2.2 Degree Diameter Primt Focus Corrector for the Blanco 4 Meter Telescope

摘要

We describe a ve element corrector for the prime focus of the 4 meter Blanco telescope at the Cerro Tololo Inter-American Observatory (CTIO) in Chile that will be used in conjunction with a new mosaic CCD camera as part of the proposed Dark Energy Survey (DES). The corrector is designed to provide a DGat focal plane and good images in the SDSS g, r, i, and z lters. We describe the performance in conjunction with the scientic requirements of the DES, particularly with regard to ghosting and weak-lensing point spread function (PSF) calibration.