Chandra Deep Field South ======================== The Chandra Deep Field South is centered on: RA(ICRS) = 03 32 28.2 Dec(ICRS) = -27 48 36 We have combined 12 CDF-S observations (ObsId = 8591, 8592, 8593, 8594, 8595, 8596, 8597, 9578, 9593, 9596, 9718, 9575) taken during Sep. - Nov. 2007. Total exposure: 980 ks. We cleaned ACIS background events in level 1 processing (by setting check_vf_pha=yes in acis_process_events to utilize a 5x5 pixel event island available in VFAINT mode), and refined astrometry based on the matched source positions and reprojected onto a common tangent plane (using a CIAO tool, reproject_aspect). The relative offsets (from obsid 9575) for individual observations are listed below for reference. The main merged data products are: acismCDFS_vf_N000_evt2.fits final merged event list for ccdid=0-3 acismCDFS_vf_N000_expmap.fits final merged exposure map acismCDFS_vf_N000_full_img2.fits full image in energy band 0.5-6 keV acismCDFS_vf_N000_colorimg.jpg true color image made with 3 energy bands (0.5-1, 1-2, 2-6 keV). We also provide the event list and aspect solution for each ObsId so that users may merge a sub-sample (e.g,. those with similar roll angles): pcad_[obsid]_reproject_asol1.fits aspect solution per observation acism[obsid]N000_reproj_vf_evt2.fits Level 2 event list per observation Table 1. Relative positional offsets of individual observations +------+-----------+-----------+-----------+--------------------------+ | | Rotation | X Transl | Y Transl | | |Obsid | Angle deg | in pixels | in pixels | date-obs | +------+-----------+-----------+-----------+--------------------------+ | 8591 | -0.002689 | -0.190693 | 0.273417 | Sep 20 2007 | | 9593 | -0.005447 | 0.016670 | 0.509791 | Sep 22 2007 | | 9718 | -0.004962 | 0.111269 | 0.188725 | Oct 3 2007 | | 8593 | -0.001654 | 0.420111 | 0.054327 | Oct 6 2007 | | 8597 | 0.000681 | 0.046893 | 0.423655 | Oct 17 2007 | | 8595 | 0.012526 | 0.251524 | 0.594546 | Oct 19 2007 | | 9575 | -0.000000 | 0.000000 | 0.000000 | Oct 27 2007 ** reference | | 8592 | -0.013634 | -0.203369 | 0.199928 | Oct 22 2007 | | 8596 | 0.016394 | -0.146683 | 0.222187 | Oct 24 2007 | | 9578 | -0.005973 | 0.057269 | -0.550306 | Oct 30 2007 | | 8594 | -0.006194 | -0.064804 | 0.297714 | Nov 1 2007 | | 9596 | 0.017150 | 0.034316 | 0.147677 | Nov 4 2007 | +------+-----------+-----------+-----------+--------------------------+ (1 pixel = 0.492 arcsec) The aspect solution and offset (by reproject_aspect) are the same as we used for the previous set of merged data at: ftp://cda.harvard.edu/pub/arcftp/cdfs2000-2007/ ftp://cda.harvard.edu/pub/arcftp/cdfs2007/ Table 2. Dates, exposure times, and roll angles of individual observations +-----+-------------+--------+-----+ | | |Exposure| Roll| |Obsid | date-obs | (ks) |(deg)| +------+-------------+--------+-----+ | 8591 | 20 Sep 2007 | 46 | 73 | | 9593 | 22 Sep 2007 | 47 | 73 | | 9718 | 3 Oct 2007 | 50 | 62 | | 8593 | 6 Oct 2007 | 50 | 62 | | 8597 | 17 Oct 2007 | 60 | 44 | | 8595 | 19 Oct 2007 | 117 | 41 | | 9575 | 27 Oct 2007 | 110 | 32 | | 8592 | 22 Oct 2007 | 88 | 32 | | 8596 | 24 Oct 2007 | 117 | 32 | | 9578 | 30 Oct 2007 | 39 | 24 | | 8594 | 1 Nov 2007 | 143 | 24 | | 9596 | 4 Nov 2007 | 113 | 20 | +------+-------------+--------+-----+