The COSMOS survey:: Hubble Space Telescope advanced camera for surveys observations and data processing

We describe the details of the Hubble Space Telescope ( HST) Advanced Camera for Surveys ( ACS) Wide Field Channel ( WFC) observations of the COSMOS field, including the data calibration and processing procedures. We obtained a total of 583 orbits of HSTACS/WFC imaging in the F814W filter, covering a field that is 1.64 deg(2) in area, the largest contiguous field ever imaged with HST. The median exposure depth across the field is 2028 s ( one HSTorbit), achieving a limiting point-source depth AB( F814W) 27: 2 ( 5 sigma). We also present details of the astrometric image registration and distortion removal and image combination using MultiDrizzle, motivating the choice of our final pixel scale ( 30 mas pixel(-1)), based on the requirements for weak-lensing science. The final set of images are publicly available through the archive sites at IPAC and STScI, along with further documentation on how they were produced.