Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.stsci.edu/science/goods/catalogs/r1.1z_readme.html
Дата изменения: Wed May 5 00:40:37 2004
Дата индексирования: Sat Dec 22 15:19:43 2007
Кодировка:
Поисковые слова: m 17
README file for GOODS Catalogs r1.0z based on v1.0 data

GOODS Source Catalogs release r1.1z based on v1.0 data

TABLE OF CONTENTS

README

1.0 General Information

On Friday, April 9 2004, at 5pm EDT, the GOODS Teams released the version r1.1 of the ACS multi-band source catalogs.

These catalogs, prepared using the SExtractor package (Bertin & Arnouts 1996, A&A 117, 393), are based on the version v1.0 of the reduced, calibrated, stacked and mosaiced images acquired with HST and ACS as part of the GOODS ACS Treasury program.

The catalogs are z-band based, that is, source detection has been made using the z-band images. A variety of photometric apertures defined during the detection process have then been used as "fixed apertures" in the i, v and b-band images to derive the multi-band photometry.

2.0 What is being released

The r1.1z release of the multi-band source catalogs comprises: eight (8) primary ASCII files (the updated catalogs); one (1) updated file required to configure SExtractor; and this "README" file.

The eight primary files are named:

Groups of letters, numbers or punctuation symbols separated by underscore ("_") are used to specify the main parameter of the catalogs.

The prefix "h" is used in the STScI multimission archive to indicate HST data products.

The second group the survey identifier.

The first letter of the following two-letter group indicates which GOODS field is catalogued (values are either "s" for GOODS-S, or "n" for GOODS-N), while the second letter indicates the photometric passband (values are "b", "v", "i" and "z").

The group "r1.1z" specifies that this is the release 1.1 of the catalogs and that detections are based on the z band.

The following group "_cat" specifies the nature of the data product (source catalog).

The extension ".txt" specifies that the catalogs consist of text ASCII files.

The updated SExtractor configuration file is

This file specifies the list of columns output by SExtractor in its photometry runs, replacing the prior release file h_goods_r1.0z_phot_param.txt. 

All other r1.0z SExtractor configuration files (listed in the r1.0z release notes) are still valid, and have not been
replaced or copied to r1.1z filenames.

We refer the reader to the original documentation provided with the SExtractor package for the meaning and content of the various configuration files.

3.0 Changes from the r1.0z release

The r1.1z release is based upon the r1.0z SExtractor run, and merely corrects errors and omissions in the r1.0z catalog files.  The catalogued sources are identical, in both number and ordering, to the r1.0z release.

The changes from r1.0z to r1.1z:
  1. Inserted the additional column ISOAREAF_IMAGE at column #17.  As per the SExtractor source code, ISOAREAF_IMAGE represents the isophotal area (filtered) above the detection threshold, while ISOAREA_IMAGE represents the isophotal area above the analysis threshold.
  2. In the GOODS-North catalogs, corrected a uniform offset in the r1.0z values of (X_MOSAIC, Y_MOSAIC) by adding (+300,+200).  This same offset applies to the coordinate pairs (XPEAK_MOSAIC, YPEAK_MOSAIC), (XMIN_MOSAIC, YMIN_MOSAIC), and (XMAX_MOSAIC, YMAX_MOSAIC).  There is no required change in these values for the GOODS-South catalogs.
  3. In the GOODS-North catalogs, corrected the values for (X_SECT,Y_SECT) and SECT_REFNUM based on the correected (X_MOSAIC, Y_MOSAIC) (see #2 above).  There is no required change in (X_SECT, Y_SECT) values for the GOODS-South catalogs.
  4. Corrected transposed values for SECT_REFNUM in all r1.0z catalogs, also taking into account adjustments in some GOODS-North SECT_REFNUM values according to #3 above.
A listing of the individual columns of the catalogs, reproduced exactly as in the catalog file headers, is provided below.
Please note that these are logical columns, not in fixed format.  Note also that a gap in the column numbering after a given parameter indicates a vector of values for that parameter spanning the proceeding, unlabelled columns (see SExtractor documentation).

4.0 Column Listing 

# 1    ID_IAU
# 2    ALPHA_J2000
# 3    DELTA_J2000
# 4    SECT_REFNUM
# 5    X_SECT
# 6    Y_SECT
# 7    X_MOSAIC
# 8    Y_MOSAIC
# 9    XPEAK_MOSAIC
# 10   YPEAK_MOSAIC
# 11   XPEAK_WORLD
# 12   YPEAK_WORLD
# 13   XMIN_MOSAIC
# 14   YMIN_MOSAIC
# 15   XMAX_MOSAIC
# 16   YMAX_MOSAIC
# 17   ISOAREAF_IMAGE
# 18   ISOAREA_IMAGE
# 19   THETA_IMAGE
# 20   ELLIPTICITY
# 21   ELONGATION
# 22   ERRTHETA_IMAGE
# 23   KRON_RADIUS
# 24   FLUX_RADIUS
# 27   FWHM_IMAGE
# 28   CLASS_STAR
# 29   FLAGS
# 30   IMAFLAGS_ISO
# 31   NIMAFLAGS_ISO
# 32   BACKGROUND
# 33   FLUX_MAX
# 34   MAG_ISO
# 35   MAGERR_ISO
# 36   FLUX_ISO
# 37   FLUXERR_ISO
# 38   MAG_ISOCOR
# 39   MAGERR_ISOCOR
# 40   FLUX_ISOCOR
# 41   FLUXERR_ISOCOR
# 42   MAG_AUTO
# 43   MAGERR_AUTO
# 44   FLUX_AUTO
# 45   FLUXERR_AUTO
# 46   MAG_BEST
# 47   MAGERR_BEST
# 48   FLUX_BEST
# 49   FLUXERR_BEST
# 50   MAG_APER
# 61   MAGERR_APER
# 72   FLUX_APER
# 83   FLUXERR_APER
# 94   X2_IMAGE
# 95   Y2_IMAGE
# 96   XY_IMAGE
# 97   ERRX2_IMAGE
# 98   ERRY2_IMAGE
# 99   ERRXY_IMAGE
# 100  A_IMAGE
# 101  B_IMAGE
# 102  ERRA_IMAGE
# 103  ERRB_IMAGE
# 104  ID_MOSAIC

5.0 Citations         

A description of the GOODS observations and data products is given in "The Great Observatories Origins Deep Survey: Initial Results from Optical and Near-Infrared Imaging" by M. Giavalisco and the GOODS Team [2004, ApJ, 600, L93].  Another paper describing in more details the GOODS HST/ACS data and source catalogs is in preparation and, for the time being, should be referenced as "M. Giavalisco and the GOODS Team, 2004, in preparation".

Back to ftp site.

Back to top of page.