galaxy_zoo_nsa_matching

Code used to match all SDSS galaxy zoo data (from GZ2 up) to the nasa sloan atlas

aggregate_gz4.py

This script is used to create the aggregated vote counts for all the sloan data in GZ4 (with metadata). Update lines 7-10 to point to where the location of the GZ4 data dumps and the subject metadata dump.

It outputs two csv files, one without the metadata and one with the metadata.

ra_dec_lookup.py

This script is used to get the RA and DEC value for the original GZ4 SDSS sample. The objids are used to look up the positions using an SQL query via astroquery.

It outputs one csv file that has objid, RA, and DEC for this subsample of GZ4 galaxies.

NOTE: this query does not work well, it only gives 123,186 matches out of 235,443 galaxies. I ended up doing a table join on casjobs to do this.

The SQL query used was:

SELECT p.ra, p.dec, p.objid into mydb.dr14_gz4_join from PhotoObjAll AS p
  INNER JOIN MyDB.GZ4_DR8 g ON g.sdss_id=p.objid

after uploading the gz4_aggregate_with_metadata.csv data table to casjobs.

gz4_to_nsa.py

This script takes the RA and DEC matches of the the previous script and does a 10 arcsec match to the NSA catalog. The resulting nsa_id values are added to the csv file output by aggregate_gz4.py. Finally the data table is reduced to only include data with nsa_ids. Update line 9 to point to where the nsa_v1_0_0.fits file is located.

It outputs two csv files, one with objid, RA, DEC, and nsa_id, and one with "nsa only" GZ4 vote counts with metadata.

gz2_to_nsa.py

This script takes the three GZ2 catalogs (specz, photoz, s82 normal) and does a 10 arcsec match to the NSA catalog.

It outputs three csv files (one for each catalog) that only includes the matched galaxies with the nsa_id column added.

label_lut.py

This script has a lookup table used to convert the column names of the GZ4 vote count table to the equivalent columns in the GZ2 data tables (and the other way around).

gz2_into_gz4_format.py

This final script brings the three GZ2 matched tables into the same format as the GZ4 vote count table and does a final sum of all vote counts based on nsa_id.

This outputs one csv file with the "all NSA galaxies seen by galaxy zoo ever" raw vote count catalog.

manga_subsample.py

This grabs the manga subsample from the NSA matched csv. It will also create a table with the nsa_id of all missing MaNGA galaxies.