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Available spectroscopic data

The major spectroscopic results are contained in a few different file structures (on SAS) and database tables (in CAS), listed below. In the case of the SAS files, the large FITS files are all line-by-line matched, so that the Nth entry in any file refers to the same object. The "plates" file, listed first below, is especially useful as a full list of the plates released. Note that the links into SAS below bring you into the full directory tree; it is best not to wander there before first reading both Understanding SDSS Spectroscopic Data and the data model.

Methods for accessing these data are summarized on the data access page. Also see the spectro pipeline page for a more complete list of spectro pipeline output files and their download locations.

Catalogs of quantities measured from Spectra
SAS locationCAS tableDescription
plates-dr9.fits(3.7 Mb)
(in SPECTRO_REDUX; see datamodel)
plateX List of all DR9 plates
(available as Yanny file too)
specObj-dr9.fits (2.9 Gb)
(in SPECTRO_REDUX;(see datamodel)
(only primaries)
Redshifts and classifications of all SDSS spectra
(also available in BOSS-only and SDSS-only versions)
ssppOut-dr9.fits (1.8 Gb)
(in SSPP_REDUX; see datamodel)
sppParams Stellar parameters from SSPP
ssppOut-dr9.lineindex.fits (2.3 Gb)
(in SSPP_REDUX; see datamodel)
sppLines Stellar line indices from SSPP
photoPlate-dr9.fits (7.9 Gb)
(in SPECTRO_REDUX; see datamodel)
join on photoObj Photometric flux-based matches
photoPosPlate-dr9.fits (7.5 Gb)
(in SPECTRO_REDUX; see datamodel)
join on photoObj Photometric position-based matches
photoMatchPlate-dr9.fits (370 Mb)
(in SPECTRO_REDUX; see datamodel)
details of match results
galSpecInfo-dr9.fits (364 Mb)
(in SPECTRO_REDUX; see datamodel)
galSpecInfo Information for each galaxy processed by Garching group
galSpecIndx-dr9.fits (1.9 Gb)
(in SPECTRO_REDUX; see datamodel)
galSpecIndx Index measurements for each galaxy
galSpecLine-dr9.fits (1.7 Gb)
(in SPECTRO_REDUX; see datamodel)
galSpecLine Line measurements for each galaxy
galSpecExtra-dr9.fits (339 Mb)
(in SPECTRO_REDUX; see datamodel)
galSpecExtra Extra physical parameters for each galaxy
Spectra Data
SAS locationCAS tableDescription
see datamodel)

Coadded spectra grouped by plate
see datamodel)

Individual spectra, one file per PLATE-MJD-FIBER
specObjAll PNG images of each spectrum