Overview
Each SDSS Data Reduction Pipeline (DRP) has a separate platelist and summary file, making it difficult to interact with “all” spectra. For DR19, a new ALLSPEC data product has been created to assemble the summary files into a single table, using the sdss_id and any pipeline-specific IDs as shown in the schema below to make it possible to collect all of the existing DRP spectra (DR8 through DR19) into the “allspec” table; and each of the plate or FPS fields that were used for the observations are combined into a “multiplex” table.
Schema
In order to connect the rows of the allspec and multiplex table, as shown in the ER diagram below (also available in PDF for clearer viewing or download), with the corresponding CAS tables that contain spectroscopic and plate or FPS field parameters, respectively, a “join” is used to connect by means of foreign keys to the corresponding tables. The foreign keys are defined as primary keys in the corresponding data reduction pipelines (as listed in the tables below); but are also included in the data analysis pipeline tables, and many of the value-added catalogs that are derived from the reduction pipelines.
Foreign Keys for allspec
| Foreign Table | Column to Join |
| DR19 BHM spAll | specobjid |
| DR17 SDSS/eBOSS SpecObjAll | specobjid |
| DR19 MWM apogee_drp_allstar | sdss_id |
| DR19 MWM apogee_drp_allvisit | file |
| DR17 apogeeStar | apstar_id |
| DR17 apogeeVisit | visit_id |
| DR17 mangaDRPall | mangaid |
Foreign keys for multispec
| Foreign Table | Columns to Join |
| DR19 BHM fieldlist* | field, mjd, run2d |
| DR17 SDSS/eBOSS PlateX | plate, mjd, run2d |
| DR17 apogeePlate | plate, mjd, apred_vers |
| DR17 MaNGA platelist* | plate, mjd, drpver |
** The DR17 MaNGA platelist is currently only available on the SAS (platelist-v3_1_1.fits).
Access
There are currently 3 ways to work with the ALLSPEC data product via:
- The CAS by running SQL commands in SkyServer http://skyserver.sdss.org/public/SearchTools/sql by selecting the allspec or multiplex table, and joining to the DRP summary files to extract parameters.
- The SAS by navigating to https://dr19.sdss.org/sas/dr19/spectro/allspec/1.0.1
- SciServer compute which has a copy of the SAS for all data releases, including DR19.
The datamodels for the fits files are available here:
with the allspec version 1.0.1 for DR19.