=========================================================================== COSMOS CFHT Data Version 2.0 =========================================================================== The Cosmic Evolution Survey (COSMOS) is an HST Treasury Project to survey a 2 square degree equatorial field, centered on RA=10:00:28.6 and DEC=+02:12:21.0, using the ACS camera. The project also incorporates major commitments from other observatories around the world, including the VLA radio telescope, ESO's VLT in Chile, ESA's XMM X-ray satellite, and the Japanese 8-meter Subaru telescope in Hawaii. These data represent one epoch of imaging on CFHT in i* band. These data are NOT psf homogenized. The filter transmission profile is included in the file CFHT_filter_i.txt. If you use these data in your work, please cite it as follows as follows: McCracken, H.J., Capak, P., Salvato, M., et al. 2010, ApJ, 708, 202 The i* band data were used to define the COSMOS astrometric system. The absolute astrometry of these data are tied to the VLA observations of the COSMOS field (Schinnerer et. al. 2004). The astrometry of all other optical and IR data, including the HST images, are tied to this image. If datasets cover regions outside of this image, the Sloan Digital Sky Survey (SDSS) astrometry, corrected to the absolute COSMOS VLA frame, is used. The key characteristics of these data are: Telescope: Canada-France-Hawaii 3.6m Telescope Instrument: MegaPrime Effective Wavelength: 768.4nm Filter Width: 138.0nm Flux unit: nJy Zero Point 31.4 Area: ~4 sq degrees Resolution: 0.15"/pix Seeing: 0.94" PSF Homogenized: NO The data products available here include the following at each of 144 tiled positions: 1) an image in units of nJy 2) a map of the image RMS in units of nJy A tile diagram is included with the data. These data were reduced by Henry J. McCracken (hjmcc@iap.fr) and the TERAPIX team (terapix@iap.fr) using the ELIXIR and TERAPIX pipelines. SWarp v.2.15 and Terapix software from 2004-12-16 were used for the reduction. Information on Elixir can be found at: http://www.cfht.hawaii.edu/Instruments/Elixir/ Information on Terapix can be found at: http://terapix.iap.fr/ These data were prepared for release by: Peter Capak (capak@astro.caltech.edu) Patrick Shopbell (pls@astro.caltech.edu) Further information may be obtained from the COSMOS web page: http://cosmos.astro.caltech.edu/ =========================================================================== April 27, 2006