How do I use the MaNGA Catalog drpall File?
The drpall file
The drpall-v2_1_2 file is a summary file from the MaNGA Data Reduction Pipeline (DRP). This table contains target and observational information (e.g., number of exposures, IFU size, identifiers), as well as galaxies properties taken from the NSA catalog, such as redshift and photometry for all the galaxies in the current data release. The datamodel for the drpall file can be found here.
Accessing the drpall file with Python
Astropy primer for working with table data
import numpy as np from astropy.io import fits drpall = fits.open('drpall-v2_1_2.fits') tbdata = drpall[1].data # Print column names tbdata.columns.names
Find the redshift of a galaxy:
ind = np.where(tbdata['mangaid'] == '12-193481')
print('redshift =', tbdata['nsa_z'][ind][0])
ind = np.where(tbdata['mangaid'] == '12-193481') print('redshift =', tbdata['nsa_z'][ind][0])
Accessing the drpall file with IDL
The drpall file can be read in using for example MRDFITS. This will put the data into an IDL structure.
t=mrdfits('drpall-v2_1_2.fits',1,hdr) ; Print column names help,t,/str
Find the redshift of a galaxy:
ind = where(t.mangaid eq '12-193481')
print,'redshift =', t[ind].nsa_z
ind = where(t.mangaid eq '12-193481') print,'redshift =', t[ind].nsa_z
Accessing the drpall file with CAS
The drpAll file exists as a table in CAS. You can query the drpall table under the Query tab in CASjobs. For example, to find all galaxies with redshift > 0.05 and stellar mass <1e10:
SELECT mangaid, objra, objdec, nsa_z, nsa_sersic_mass FROM dbo.mangaDrpAll where nsa_z > 0.05 and nsa_sersic_mass < 1e10