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------------------------------ Uchuu-SDSS lightcones ------------------------------
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Uchuu-SDSS lightcones with ugriz magnitudes, stellar masses and SSFRs. Galaxies in the mock are assigned r-band magnitudes and g-r colours. To assign the magnitudes, the SDSS galaxy closest in magnitude, colour and redshift is found.

If you use the Uchuu-SDSS galaxy lightcones, please cite the following paper:

"Uchuu-SDSS galaxy lightcones: a clustering, RSD and BAO study by Dong-Páez, CA. et al. (2022)"
https://ui.adsabs.harvard.edu/abs/2022arXiv220800540D/abstract

Then, please consider adding this text to the Acknowledgements section of your paper(s):
http://www.skiesanduniverses.org/Simulations/Uchuu/UchuuCredits/

------------------------------ Reading the files -----------------------------

Datasets can be read from the file in Python by doing, e.g.

# read in ra, dec, z and absolute r-band magnitude
import h5py
f = h5py.File("mock_0.hdf5","r")
ra = f["Data/ra"][...]
dec = f["Data/dec"][...]
z_obs = f["Data/z_obs"][...]
M_r = f["Data/M_r"][...]
f.close()

-------------------------------- Random file --------------------------------

The random file contains 10x the number of galaxies. Galaxies are randomly sampled from the mock, and positioned uniformly on the sky. The properties of each random galaxy are the same as for the corresponding galaxy in the data mock (except for the random ra and dec, and the completeness, which depends on its new ra,dec coordinates)

-------------------------------- Footprint --------------------------------

The full footprint has an area 7261 sq deg

When cutting to regions with fibre assignment completeness > 0.9, the area is 6642 sq deg

---------------------- Description of galaxy properties ----------------------

The following datasets are stored in each hdf5 file:

Data/First_Acc_Scale
Scale factor when current and former satellites first passed through a larger halo

Data/M_g
Rest-frame g-band absolute magnitude, k-corrected to z=0.1 (from closest SDSS galaxy)

Data/M_i
Rest-frame i-band absolute magnitude, k-corrected to z=0.1 (from closest SDSS galaxy)

Data/M_r
Rest-frame r-band absolute magnitude, k-corrected to z=0.1 (from mock)

Data/M_r_fib
recomputed r-band absolute magnitude based on values of kcorr_r_fib and z_obs_fib (same as abs_mag for galaxies with spectro z's) (**NOTE - this is not evolution corrected)

Data/M_u
Rest-frame u-band absolute magnitude, k-corrected to z=0.1 (from closest SDSS galaxy)

Data/M_z
Rest-frame z-band absolute magnitude, k-corrected to z=0.1 (from closest SDSS galaxy)

Data/Macc
Halo mass at accretion, in units Msun/h. The halo mass is defined as Mvir (Mass enclosed within the viral overdensity, bound particles only)

Data/Mvir_all
Mass enclosed within the viral overdensity, including unbound particles, in units Msun/h

Data/Rvir
Virial radius, in units kpc/h

Data/Vpeak
Peak value of Vmax over the accretion history, in physical km/s

Data/completeness
Fibre-collision completeness in the HEALPIX pixel this galaxy falls within. This completeness is averaged over all 32 mocks, and uses a pixelation with nside=512

Data/dec
Declination (degrees)

Data/g_r
Rest-frame g-r colour, k-corrected to z=0.1 (from mock)

Data/g_r_obs
Observer-frame g-r colour (from mock)

Data/galaxy_type
Galaxy type, where 0=central galaxy and 1=satellite galaxy

Data/halo_id
Original halo id from the Uchuu simulation

Data/halo_mass
Host halo mass, M200crit, in units Msun/h

Data/idnn
ID of nearest neighbor in original catalog (-1 if no galaxies are within 55''; -2 if galaxy collided but still keeps its true redshift)

Data/is_cen
Indicates if a galaxy is a central (True) or satellite (False)

Data/is_collided
Indicates if a galaxy is fibre-collided (is True if idnn is not either -1 or -2)

Data/kcorr_g
g-band k-correction, to convert apparent mag to absolute mag (at z=0.1) (from closest SDSS galaxy)

Data/kcorr_i
i-band k-correction, to convert apparent mag to absolute mag (at z=0.1) (from closest SDSS galaxy)

Data/kcorr_r
r-band k-correction, to convert apparent mag to absolute mag (at z=0.1) (from closest SDSS galaxy)

Data/kcorr_r_fib
k-correction; original for galaxies with spectro redshifts; recomputed for galaxies assigned nearest neighbor redshifts

Data/kcorr_u
u-band k-correction, to convert apparent mag to absolute mag (at z=0.1) (from closest SDSS galaxy)

Data/kcorr_z
z-band k-correction, to convert apparent mag to absolute mag (at z=0.1) (from closest SDSS galaxy)

Data/m_g
g-band apparent magnitude (calculated using the absolute magnitude and k-correction from SDSS, but with the redshift of the galaxy in the mock)

Data/m_i
i-band apparent magnitude (calculated using the absolute magnitude and k-correction from SDSS, but with the redshift of the galaxy in the mock)

Data/m_r
r-band apparent magnitude (from mock)

Data/m_u
u-band apparent magnitude (calculated using the absolute magnitude and k-correction from SDSS, but with the redshift of the galaxy in the mock)

Data/m_z
z-band apparent magnitude (calculated using the absolute magnitude and k-correction from SDSS, but with the redshift of the galaxy in the mock)

Data/pid
Is equal to -1 for central galaxies, a positive integer for satellites. Satellite galaxies in the same halo all have the same value of pid

Data/pos
3D position vector (comoving Mpc/h). Note that this is not the same as the coordinates in the cubic box. The coordinates where shifted so that the observer is at the origin, and the coordinates were also rotated on the sky when cutting to the SDSS footprint. It also includes periodic replications, so the coordinate in each direction can be larger than the box size.

Data/ra
Right ascension (degrees)

Data/rs
NFW scale radius, in kpc/h

Data/snap
Snapshot number from Uchuu

Data/ssfr_MPA
MPA specific star formation rate, log(1/Gyr)

Data/ssfr_granada_best
Best-fitting Granada specific star formation rate, log(1/Gyr)

Data/ssfr_granada_median
Median Granada specific star formation rate, log(1/Gyr)

Data/stellar_mass_MPA
MPA stellar mass (Mpc/h^2)

Data/stellar_mass_granada_best
Best-fitting Granada stellar mass (Mpc/h^2)

Data/stellar_mass_granada_median
Median Granada stellar mass (Mpc/h^2)

Data/vel
3D velocity vector, in physical km/s

Data/vrms
Velocity dispersion in physical km/s

Data/z_cos
cosmological redshift (ignoring velocities)

Data/z_obs
observed redshift (including peculiar velocity)

Data/z_obs_fib
For collided galaxies without spectroscopic redshifts, the redshift (z_obs) of their nearest neighbor. For galaxies which do have spectroscopic z's, this is just z_obs.