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Core Data Sets for GOODS Science Demo at JBO 01/03
In order to prepare a stand-alone AVO demo setup a subset of the GOODS data and VizieR catalogs is selected. This subset will be deployed on the demo machine at JBO and used as a reference for testing.
Purpose of this Page
- prioritized list of mandatory catalogs, data sets, other data items ...
- info on how to access each data item in Aladin, SED, ACE, etc.
- serve as check list for testing
- guideline which data to use for PR material
Catalogs
| Priority | Specifier | Name in Aladin/VizieR | Details |
|---|
| 1 | ESO EIS UBVRI draft cross-matched | II/234/ubvri | also accesible as "eis-cc" in Aladin/VizieR (UBVRI and UBVRIJK) |
| 2 | ESO EIS UBVRIJK draft cross-matched | II/234/ubvrijk | also accesible as "eis-cc" in Aladin/VizieR (UBVRI and UBVRIJK) |
| 3 | ESO EIS UBVRI single band | J/A+A/379/740 | accessible as "eis" in Aladin |
| | note the individual EIS single band catalogs can be loaded individually as J/A+A/379/740/v etc. | |
| 4 | Giacconi et al, Chandra/WFI | | docs, ApJ, 551, 624 |
| 5 | ??? | | - |
Catalogs - HDF(N) and HFF
See HDFNorthNotes and Sky Coverage
Data Sets
*See VLADataCDFS
Data Sets - HDF(N) and HFF
See HDFNorthNotes for references and DataForAVO for links to the original data and descriptions.
All data should be on the ICRF as described in Astrometry and Photometry for the HDF(N)
with the reference pixel (CRVAL1, CRVAL2) at 12 36 49.4 +62 12 58
All data have CTYPE1 = RA---SIN, CTYPE2 = DEC--SIN, CTYPE3 = FREQ
and all are square (in projection) with N at the top and E at the left.
CRPIX3 = 1 and BUNIT = Jy/pixel
Other quantities are given for each data set or group. DATE-OBS is given in each header but is not necessarily useful as some observations covered days, weeks or months.
All HDF(N) data matched to CHANDRA resolution 1024 x 0".492 (CDELT1, CDELT2) CRPIX1 = 520, CRPIX2 = 504
High resolution HST and radio data 8192 x 0".0625 (CDELT1, CDELT2) CRPIX1 = 4096, CRPIX2 = 4097
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
| HST | F814W I | data | 3.7758E14 | 7.3469E13 | 7.3469E13 | 0.16 | 4sigma (1.3-9)E-9 | (3-23)E-7 | S, Y |
| MERLIN+VLA | L 1.4 GHz | data | 1.40005E9 | 7E7 | 4.375E7 | 0.4 | 7sigma ~24E-8 | 1.5E-4 | S?, N |
The high-resolution HST and radio images (8192 x 0".0625 pixels) are
also available as 1024 x 0".0625 pixel HDF(N) HighresCutouts
(1) See Sky Coverage - the MERLIN+VLA and CHANDRA data extend to a larger region at lower sensitivity.
(2) Conventional band label
(3) The data in these forms are not yet in Aladin/Vizier. They could be incorporated (e.g. in MERLIN Archive format) or accessed as 'local'.
(4) Central frequency CRVAL3 (may differ from conventional label for observing frequency)
(5) Total b/w (CDELT3 for all except radio)
(6) Effective b/w used to scale flux density, if different (radio CDELT3)
(7) This is approximately the diameter of an aperture enclosing ~67%
of the power detected by the instrument beam (or its equivalent after
data processing to enhance resolution), and is the minimum sensible
re-extraction radius. An aperture 2xFWHM in diameter would enclose
~95% of the power for Gaussian beams, see references/links for the
actual shapes. If an aperture of between 1-2 FWHM is used the user
could apply a correction to compensate for the missing flux. Note that
radio and optical images show that nearly all sources are at least 1"
- 2" across.
(8) The detection threshold (after subtraction of any background) is
taken from the references and scaled to Jy/pixel, after making
allowances for changes in noise due to resampling for the radio data.
In other cases special techniques may be needed to reach this; in
particular we may not be able to re-extract ISO sources without using
a template. In every case the appropriate aperture should be used,
and a suitable minimum number of pixels above the threshold, e.g. the
number across the PSF for a 3-4 sigma cutoff (e.g. HST), or a single
pixel using a 5-7 sigma cutoff (e.g. radio).
(9) As (8) in Jy/asec2.
(10)
The detection threshold changes by a large factor across the ISO
fields and between the HDF and HFF, and by a few percent across the
other fields. The ISO variance maps are supplied and SExtractor can
generate maps for the other fields as needed. It is customary not to
subtract a background from the radio images due to the properties
arising from the FT and CLEANing.
V = Variance map supplied
S = Use SExtractor to create variance map if needed
Y = Subtract background
N = Conventionally do not subtract background
SExtractor templates
Are sample .sex files needed?
Templates prepared from the HDF(N) catalogues (listed above) for use in SExtractor. Note that ~1/3 of CHANDRA and radio sources fall outside the image regions available here. Each template consists of a 1024 x 0".492 map with Gaussian point sources at the position of each source in the specified catalogue (CATAMAP). These can be used with a user-specified aperture to extract flux measurements from any real data at the same pixel scale and reference (CDELT1, CDELT2, CRPIX1, CRPIX2, CRVAL1, CRVAL2), i.e. the first group of HDF(N) data. Control templates are also provided in which all the positions have been shifted by 10" to the NE (CATSHIFTMAP). There is no template for the HST data because of the source density 10x greater than the other catalogues and because SExtractor should be able to identify souces in these data most reliably anyway.
NB Use the CATAMAPs as position templates only, their flux densities are meaningless. Flux densities should only be measured from the real maps listed above or taken from the catalogues.
To AVO team members:
Contact Jonas Haase for issues related to data.
Do not hesitate to add complementary information like Aladin/VizieR descriptors (e.g. II/234), limiting magnitudes and so forth whenever possible.
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