Detail of the AXAF Deep Field

Image showing a small area of the AXAF Deep Field at the original resolution. It measures about 5.8 x 6.5 arcmin 2, i.e. the area corresponds to approx. 1/30 of the full frame. The background is extremely crowded with very faint objects - most of these are galaxies at very large distances. Some of them are likely to be identified as strong X-ray emitters when this field is observed with the Chandra X-ray Observatory.

Twenty-eight exposures with a total integration time of 7 hours have been co-added. After each single exposure, the telescope was offset by a small angle in order to cover also the gaps between the eight CCD's in the mosaic and to enable removal of minor cosmetical blemishes of the detectors. Since the CCD mosaic of the WFI comprises 67 million pixels, a total of 1,900 million data points was thus used to construct this image. The related image processing, using the EIS WFI data reduction pipeline, recently developed at ESO, kept a powerful workstation fully busy for about 8 hours.