++++++++++++++++++++++++++++++++++++++++++++ Galaxy quantities for ops-rehearsals 3 and 4 ++++++++++++++++++++++++++++++++++++++++++++ Data are partitioned by (nside=32, ring ordering) healpixel. For each pixel there is a so-called "main file" (with information largely coming from the cosmodc2 galaxy catalog) and a flux file. The latter contains for each object only fluxes for lsst bands and the object id so it can be joined with the main file. Both are parquet files. The main file can be rather large (over 3 Gbytes) so, depending on your application, you may want to iterate over row groups rather than reading it all in at once. Galaxy main file ---------------- ======================== ============ ============== ======================== Name Datatype Units Description ======================== ============ ============== ======================== galaxy_id int64 N/A Unique object identifier ra double degrees Object right ascension dec double degrees Object declination redshift double N/A Cosmological redshift with line-of-sight motion redshift_hubble double N/A Cosmological redshift peculiar_velocity double km/sec Peculiar velocity shear_1 double N/A Shear (gamma) component 1, treecorr/Galsim convention shear_2 double N/A Shear (gamma) component 2, treecorr/Galsim convention convergence double N/A Convergence (kappa) size_bulge_true float arcsec Bulge half-light radius (major axis) not lensed size_minor_bulge_true float arcsec Bulge half-light radius (minor axis) not lensed sersic_bulge float N/A Sersic index of bulge light profile size_disk_true float arcsec Disk half-light radius (major axis) not lensed size_disk_bulge_true float arcsec Disk half-light radius (minor axis) not lensed sersic_disk float N/A Sersic index of disk light profile ellipticity_1_disk_true double N/A Ellipticity component 1 for disk, not lensed ellipticity_2_disk_true double N/A Ellipticity component 2 for disk, not lensed ellipticity_1_bulge_true double N/A Ellipticity component 1 for bulge, not lensed ellipticity_2_bulge_true double N/A Ellipticity component 2 for bulge, not lensed sed_val_bulge list(double) 4.4659e13 W/Hz Integrated rest-frame AB luminosities for tophat filters (bulge component) sed_val_disk list(double) 4.4659e13 W/Hz Like sed_val_bulge bulge_magnorm double N/A Normalization for SED disk_magnorm double N/A Normalization for SED MW_rv float N/A Extinction parameter MW_av float N/A Extinction parameter from F19 dust map sed_val_knots list(double) 4.4659e13 W/Hz Like sed_val_bulge n_knots float N/A Number of knots knots_magnorm double N/A Normalization for SED ======================== ============ ============== ======================== NOTE: For tophat definitions (start and width in units of angstroms) see yaml config file associated with the data. Galaxy flux file ---------------- ============= ========= ================ ================================ Name Datatype Units Description ============= ========= ================ ================================ galaxy_id int64 N/A Unique object identifier lsst_flux_u float photons/sec/cm^2 Flux integrated over lsst u-band lsst_flux_g float photons/sec/cm^2 Flux integrated over lsst g-band lsst_flux_r float photons/sec/cm^2 Flux integrated over lsst r-band lsst_flux_i float photons/sec/cm^2 Flux integrated over lsst i-band lsst_flux_z float photons/sec/cm^2 Flux integrated over lsst z-band lsst_flux_y float photons/sec/cm^2 Flux integrated over lsst y-band ============= ========= ================ ================================