At the IVOA meeting in Cambridge in May, one of the highest priority projects identified for the DAL working group was to define a Simple Spectral Access (SSA) protocol for accessing 1D spectra and SEDs.
To help plan this effort a little survey was conducted among potential data providers and consumers. The results are summarized below. Of course, the summary is only as complete as the response we've received. Thanks a lot to all who took the time to answer to our questions!
More feedback is always welcome. Regards,
DougTody, MarkusDolensky
- Sloan Digital Sky Survey (SDSS), Data Release 1
186.000 objects, 3800-9200 Å, 1300 square degrees, resolution 1800
- NCSA Astronomy Digital Image Library (NCSA BIMA Data Archive)
- Variety of spectral data sources from X-ray and gamma-ray missions, including both relatively high and low resolution spectral data (HEASARC)
- Indo-U.S. Library of Coude Feed Stellar Spectra (NOAO & CFLIB)
1300 spectra, 3465-9469 Å @ 0.44A/pix
- at NOAO:
- at ESO/ST-ECF as of June 26, 03
Observ./Instr. | No. of Spectra | Observ./Instr. | No. of Spectra |
---|---|---|---|
HST/ACS | ? | ESO/EMMI | 30332 |
HST/FOS | 16058 | ESO/FORS1+2 | 14721 |
HST/GHRS | 12340 | ESO/ISAAC | 66274 |
HST/NICMOS | ? | ESO/UVES | 50024 |
HST/STIS | 35766 | ESO/VIMOS | 6754 |
ESO/CES | 9272 | ESO/WFI | ? |
ESO/EFOSC2 | 11054 |
- XMM-Newton 1D Scpectral Data
XMM/RGS, 20000 spectra (expected), 0.35-2.5 keV, resolution 200-800
XMM/EPIC, 1.5 mio. spectra (expected), 0.35-15 keV, resolution 20-50
- ISO 1D Spectral Data
10000 files, 2.4-197 micron, resolution 40-30000
- IUE Newly-Extracted Spectra (INES)
110000 spectra, 9500 objects, 1150-1980 Å & 1850-3350 Å resolution 1.676 & 2.669 Å/pix
- at NAOJ/SMOKA as of Aug. 25, 03:
(National Astronomical Observatory of Japan / Subaru Mitaka Okayama Kiso Archive)
Observ./Instr. | No. of Spectra | Size | Description |
---|---|---|---|
Subaru/HDS | 2158 | 16MB | extremely high-dispersion optical echelle spectroscopy |
Subaru/IRCS | 7546 | 4MB | low-resolution and echelle spectroscopy from 1-5 microns |
Subaru/FOCAS | 3121 | 16MB | optical longslit and multi-slit spectroscopy over a 6 arcmin field of view |
Subaru/OHS | 4664 | 2MB | low-resolution spectroscopy in the near-infrared |
Subaru/COMICS | 9902 | 1.7MB | spectroscopy from 8-26 microns |
OAO/HIDES | 1390 | 16MB | extremely high-dispersion optical echelle spectroscopy |
OAO/SNG | 8441 | 0.3MB | low-resolution optical spectroscopy |
OAO : 188cm telescope at Okayama Astronomical Observatory
Subaru : 8.2m optical-infrared telescope at the summit of Mauna Kea
- Hyperleda
10000 reference spectra of stars and galaxies, resolution 300 - 1000000, 1300 Å - 2.5 microns
total volume 5 GB, collected from literature and reformatted
- Elodie
25000 extracted echelle spectra, resolution 42000, 4000 - 6800 Å
on the fly processing options available: wavelength resampling, flux calibration etc.
total volume 50 - 100 GB
Columns/data items:
Yes. Data are generally on-line, but proprietary periods and restricted access depending on nationality may apply.
Tools for SEDs:
see, for instance http://www.stsci.edu/resources/software_hardware/specview/what_is_specview
FITS (images, tables), XML, and plain ASCII are all supported by Specview at this point. It is fairly easy to write ingestor modules for almost any conceivable spectral format that uses one of those media.
An interesting service would be to generate 1-D spectra from cubes on the fly. In addition to the usual search parameters, users would have to provide a spatial resolution. This service would be analogous to an image cutout service in that the output is generated to user specs on-the-fly from the underlying data. (Ray Plante)
Even at this level of detail it may be inappropriate to discuss the HEASARC monolithically. The characteristics of individual missions/instruments varies enormously. (Tom McGlynn)
1D and 2D currently have more applications than 3D. FITS binary tables format and support under development. Will be evolved to support VO spectral standards. (Francisco Valdes)
[...] the different storage formats and associated data tables would provide for some interesting use cases. Something like a cutout service might be appropriate for some of the data, the challenging thing for us however to put all these into an SSA is simply the variety of local data access methods required. (Mike Fitzpatrick)
I | Attachment | History | Action | Size | Date | Who | Comment |
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ssadass.pdf | r1 | manage | 1944.6 K | 2003-10-09 - 15:10 | MarkusDolensky | A0 Poster of SSA Survey |
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