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Mock SDSS Catalogs From Tinker 2020 (Algorithm & Tests)

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sham_mockA.rdz

This is an ascii file containing 'mockA' from the Tinker 2020 self-calibrating group finder paper 'Algorithm and Tests'.

  1. RA [degrees; float] - right ascension.

  2. Dec [degrees; float] - declination

  3. z [float] - redshift of the galaxy

  4. Log L_gal [float] - log of the r-band luminosity, in solar luminosities

  5. color_flag [float] - 1==quiescent, 0==star-forming

  6. L_sat [L_sol; float] - total satellite luminosity (central galaxies only)

  7. Log M_halo [float] - halo mass from the rockstar halo catalog. For satellite galaxies, this is the halo mass of the host halo (not the subhalo)

  8. haloid [int] - halo ID.

  9. halo_upid [int] - halo ID of host halo (-1 if a central galaxy)

groups_mockA.out

This is an ascii file. The file is line-by-line parallel with the sham_mockA.rdz input file. The fields in the file are:

  1. id [int] - 0-indexed list of galaxies. This values should go in order from 0 to NGAL-1.

  2. RA [degrees; float] - right ascension of the galaxy

  3. Dec [degrees; float] - decliration of the galaxy

  4. z [float] - redshift of the galaxy

  5. L_gal [L_sol/h^-2; float] - r-band luminosity of the galaxy in solar units, assuming M_r,sol=4.65 and h=1.

  6. V_max [(Mpc/h)^3; float] - maximum volume at which each galaxy can be observed in SDSS. Taken from NYU VAGC

  7. P_sat [float] - probability that this galaxy is a satellite. If P_sat>0.5, it is assumed to be a satellite and will be assigned to a group with a different central galaxy.

  8. M_halo [M_sol/h; float] - Halo mass that the galaxy is assigned to. If the galaxy is a satellite, this is the parent halo's mass.

  9. N_sat [float] - If the galaxy is a central (P_sat<0.5), this is the number of satellites within that halo. This is a float rather than an int becuase, for volume-limited samples, this number is corrected for redshift boundaries using an error function.

  10. L_tot [L_sol/h^2; float] - The total luminosity of the group that the galaxy occupies.

  11. igrp [int] - The id of the central galaxy for the group (column 1). If the galaxy is a central, igrp=id. This is also the 0-indexed line of the file.

sham_mockB.rdz

This is an ascii file containing 'mockB' from the Tinker 2020 self-calibrating group finder paper 'Algorithm and Tests'. As discussed in the paper, the main difference with mockA is that mockB contains an extra paramer, chi, which correlates with M_halo at fixed L_gal.

  1. RA [degrees; float] - right ascension.

  2. Dec [degrees; float] - declination

  3. z [float] - redshift of the galaxy

  4. Log L_gal [float] - log of the r-band luminosity, in solar luminosities

  5. color_flag [float] - 1==quiescent, 0==star-forming

  6. chi [float] - normalized galaxy secondary property, chi. This value is Gaussian distributed about zero with unit dispersion. The correlation coefficient of chi with M_h is r-square=0.87.

  7. L_sat [L_sol; float] - total satellite luminosity (central galaxies only)

  8. Log M_halo [float] - halo mass from the rockstar halo catalog. For satellite galaxies, this is the halo mass of the host halo (not the subhalo)

  9. haloid [int] - halo ID.

  10. halo_upid [int] - halo ID of host halo (-1 if a central galaxy)

groups_mockB.out

This is an ascii file. The file is line-by-line parallel with the sham_mockA.rdz input file. The fields in the file are:

  1. id [int] - 0-indexed list of galaxies. This values should go in order from 0 to NGAL-1.

  2. RA [degrees; float] - right ascension of the galaxy

  3. Dec [degrees; float] - decliration of the galaxy

  4. z [float] - redshift of the galaxy

  5. L_gal [L_sol/h^-2; float] - r-band luminosity of the galaxy in solar units, assuming M_r,sol=4.65 and h=1.

  6. V_max [(Mpc/h)^3; float] - maximum volume at which each galaxy can be observed in SDSS. Taken from NYU VAGC

  7. P_sat [float] - probability that this galaxy is a satellite. If P_sat>0.5, it is assumed to be a satellite and will be assigned to a group with a different central galaxy.

  8. M_halo [M_sol/h; float] - Halo mass that the galaxy is assigned to. If the galaxy is a satellite, this is the parent halo's mass.

  9. N_sat [float] - If the galaxy is a central (P_sat<0.5), this is the number of satellites within that halo. This is a float rather than an int becuase, for volume-limited samples, this number is corrected for redshift boundaries using an error function.

  10. L_tot [L_sol/h^2; float] - The total luminosity of the group that the galaxy occupies.

  11. igrp [int] - The id of the central galaxy for the group (column 1). If the galaxy is a central, igrp=id. This is also the 0-indexed line of the file.

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