=========================================================================== COSMOS Chandra Data (X-ray band) 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, NASA's Chandra X-ray Observatory and the Japanese 8-meter Subaru telescope in Hawaii. These data represent the first public release of the COSMOS observations from the ACIS instrument on Chandra. Included in this release are Chandra standard data products from the archive and subsequent derived products that are required in X-ray image and spectral data analysis. The key characteristics of these data: Instrument: Chandra ACIS-I Dates of observations: (Nov 2006 - Jun 2007) Observing time: 1.8 Msec Energy band: 0.5 - 7 keV Area: 0.9 sq deg Resolution: 0.5"/pixel These data were reduced primarily by Tom Aldcroft (taldcroft@cfa.harvard.edu) using the CIAO software tools (http://cxc.harvard.edu/ciao/) and a fully-automated reduction pipeline implemented with yaxx (http://cxc.harvard.edu/contrib/yaxx/). Nico Cappelluti and Antonella Fruscione also made significant contributions. The data products are organized hierarchically for each Chandra observation and include: (1) X-ray event files (custom processed with fine astrometry corrections) (2) Exposure maps for each CCD and X-ray band (full, soft, hard) (3) Supporting data products (bad pixel, aspect solution, etc) (4) Celldetect and wavedetect source lists (per-CCD) (5) Source and background extraction region files The files follow a standard naming scheme: File type Description File name ----------------- ------------------------------------ ------------------------- obs_dir Directory for observation obsid obs/ obs_asol Corrected aspect solution file obs/asol1.fits obs_uncor_asol Original asol file (SDP level-1) obs/uncor_asol1.fits obs_evt1 Event file (SDP level-1) obs/acis_evt1.fits obs_evt2 Level-2 event file obs/acis_evt2.fits obs_pbk0 Parameter block file (SDP level-0) obs/acis_pbk0.fits obs_bias0 Bias map (SDP level-0) obs/acis_bias0.fits obs_fov1 Field of view file (SDP level-1) obs/acis_fov1.fits obs_msk1 Instrument mask file (SDP level-1) obs/acis_msk1.fits obs_mtl1 Mission timeline file (SDP level-1) obs/acis_mtl1.fits obs_flt1 Good time interval file (SDP level-1) obs/acis_flt1.fits obs_bpix1 Bad pixel file (SDP level-1) obs/acis_bpix1.fits obs_src2 Celldetect source list (SDP level-2) obs/acis_src2.fits obs_img JPEG image of obs_evt (0.5-7 keV) obs/acis_img.fits obs_acisi_img FITS image of ACIS-I (0.5-7 keV) obs/obsacis_0123_img.fits obs_acisi_img JPEG image of ACIS-I (0.5-7 keV) obs/obsacis_0123_img.jpg obs_celldet_filt_src Source list from celldetect obs/celldet_filt_src.fits obs_asphist Aspect histogram for obsid obs/asphist.fits ccd_dir Directory for one band of one CCD obs/ccd/ ccd_img JPEG image for CCD (0.5-7 keV) obs/ccd//acis_img.fits ccd_evt Events for one band of one CCD obs/ccd//acis_evt2.fits ccd_instmap Instrument map (one CCD band) obs/ccd//instmap.fits ccd_expmap Exposure map (one CCD band) obs/ccd//expmap.fits celldet_src Celldetect source list (one CCD band) obs/ccd//celldet_src.fits celldet_filt_src Celldetect source list (filtered) obs/ccd//celldet_filt_src.fits wavdet_src Wavdetect source list (one CCD band) obs/ccd//wavdet_src.fits wavdet_scell Wavdetect source cells (one CCD band) obs/ccd//wavdet_scell.fits wavdet_imgfile Wavdetect source image (one CCD band) obs/ccd//wavdet_imgfile.fits wavdet_nbkg Wavdetect background (one CCD band) obs/ccd//wavdet_nbkg.fits src_dir Directory for one detected source obs/ccd//src src_img JPEG image of source evts (0.5-7 keV) obs/ccd//src/acis_img.fits src_reg Source extraction region obs/ccd//src/src.reg bkg_reg Background region obs/ccd//src/bkg.reg Further information may be obtained from the main COSMOS web page: http://cosmos.astro.caltech.edu/ and the Chandra-COSMOS web page: http://chandracosmos.cfa.harvard.edu/ =========================================================================== The COSMOS Team, Patrick Shopbell (Archive Lead), and Tom Aldcroft pls@astro.caltech.edu, taldcroft@cfa.harvard.edu July 22, 2008