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----- Galaxy lightcones for BOSS and eBOSS Surveys ------
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Uchuu simulation:

A total of 16 high fidelity lightcones are generated using the Uchuu simulation: a high-resolution
 N-body simulation with box size 8(Gpc/h)**3 that follows the evolution of 2.1 trillion dark matter
 particles assuming Planck-LCDM cosmology. The Uchuu (sub)halos are populated assuming the number-density 
and redshift distribution of Luminous Red Galaxies (LRG) using the subhalo abundance matching technique. 

GLAM simulations:

We release a set of ~16000 lightcones based on ~2000 realizations of the GLAM N-body code. GLAM simulations
are done for the same Planck-LCDM cosmology as the Uchuu simulaion. LRG are added using the halo occupation
 distribution (HOD) method with parameters  

Overall, our lightcones reproduce a large number of observed statistical properties of galaxies for
 redshifts z=0.2-1.0 and for scales  (2 -150)Mpc/h, and wavenumbers k=(0.005-0.7)h/Mpc including
 the footprint, redshift evolution, and clustering dependence on stellar mass. 
 We also recover the large-scale bias factor, finding that it increases with redshift:
 b_(z=0.3)=1.81, b_(z=0.57)=2.00, b_(z=0.8)=2.22.

Finally, to further investigate the effect that cosmology has on galaxy clustering, we provide 800 lightcones
 using GLAM simulations of different cosmologies: GLAM-PMILL, GLAM-PMILLnoBAO and GLAM-Abacus, 
finding that, with the present data uncertainties, all studied cosmologies can explain the observed
 distribution of galaxies.

For more infomartion about the generation process of these lighcones, see: https://arxiv.org/abs/2311.14456

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

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

# read in ra, dec, z and atellar mass of Uchuu-CMASS-N lightcone:
import h5py
f = h5py.File("CMASS_N_Uchuu_0.dat.h5","r")
ra = f["ra"][:]
dec = f["dec"][:]
z_obs = f["z_obs"][:]
Mstll = f["logMstll"][:]
f.close()


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

===== Uchuu lightcones ====

Each Uchuu lightcone has the following columns:
    --> {ra}: right ascension (degrees).
    --> {dec}: declination (degrees).
    --> {z_cos}: cosmological redshift.
    --> {z_obs}: observed redshift (accounting for peculiar velocities).
    --> {nz}: number density of galaxies, n(z), at the redshift of the galaxy (h^3/Mpc^3).
    --> {logMstll}: logarithm (log_10) of the galaxy stellar mass (M_sun).
    --> {poly_id}: healpix pixel ID containing the galaxy.
    --> {poly_w}: fibre-collision completeness in the healpix pixel containing the galaxy.
    --> {w_cp}: fibre collision correction weight (NNW).
    --> {w_fkp}: FKP weight.
    --> {w_npcf}: only in COMB sample lightcones. Extra weight to adjust the contribution of each sample (LOWZ and CMASS). 
    
In addition, the following columns describe the properties of the DM host halos (and subhalos) of galaxies. These are taken from the original values in the Uchuu} simulation halo catalogues:
    --> {Mvir_all}: mass enclosed within the virial overdensity, including unbound particles (M_sun/h).
    --> {Rvir}: virial radius (kp/h).
    --> {rs}: scale radius of a fitted NFW profile (comoving  kp/h)
    --> {Cvir}: dark matter concentration within Rvir.
    --> {Vpeak}: peak value of V_max over the halo history (physical km/s).
    --> {id}: ID that identify each (sub)halo (unique in the whole simulation).
    --> {pid}: ID of the parent central halo for satellite haloes, -1 for central haloes.
    --> {x, y, z}: 3D position coordinates. The coordinate system of the Uchuu cubic box has been shifted so that the observer is at the origin, and there are periodic replications of the box (comoving  Mpc/h).
    --> {vx, vy, vz}: 3D velocity (physical km/s).
    --> {vrms}: velocity dispersion (physical km/s).
    --> {vlos}: velocity vector projected along line-of-sight, with the observer positioned at the origin (km/s).

In general, the weight of the galaxies will be "w_cp".
For clustering calculations (2PCF, 3PCF, P(k)...), it should be "w_total = w_cp * w_fkp (* w_npcf)".

Random catalogues, containing 40 times the number of galaxies of an individual catalogue, are also provided.
Note that in randoms, the nz values are not calculated with the number of random galaxies, but it coincides with the nz of the dat files. The w_fkp is calculated based on this nz.

Within the Uchuu folder there is a subfolder called "fullsky_lightcones". These are the lightcones used for the generation of the final Uchuu lightcones. These cover the entire sky area, they have *no* acceptance masks, veto masks, fiber collision, completeness cut, or any other kind of systematics applied. The columns of these files are the same as described above. 


===== GLAM lightcones ====

Each GLAM lightcone has the following columns:
    --> {gal_id}: indicates whether the galaxy is central or a satellite (1 for centrals, 2 for satellites).
    --> {ra}
    --> {dec}
    --> {z_obs}
    --> {nz}
    --> {logMstll}
    --> {poly_id}
    --> {poly_w}
    --> {w_cp}
    --> {w_fkp}
    --> {w_npcf}

In addition, the following columns describe the DM host halo (not subhalos) properties of galaxies, taken from the original values found in the GLAM simulation halo catalogues,
    --> {Mtotal}: halo virial mass (\hMsun).
    --> {Rvir}
    --> {rs}

In general, the weight of the galaxies will be "w_cp".
For clustering calculations (2PCF, 3PCF, P(k)...), it should be "w_total = w_cp * w_fkp (* w_npcf)".

Random catalogues, containing 30 times the number of galaxies of an individual catalogue, are also provided.
Note that in randoms, the nz values are not calculated with the number of random galaxies, but it coincides with the nz of the dat files. The w_fkp is calculated based on this nz.



===== BOSS and eBOSS samples ====

In order to facilitate any analysis, we also make available the observed galaxy samples used is this work. The columns are as follows: 
    --> {RA}: right ascension (degrees).
    --> {DEC}: declination (degrees).
    --> {Z}: measured redshift, including fibre collisions (h^3/Mpc^3).
    --> {NZ}: number density of galaxies, n(z), at the redshift of the galaxy.
    --> {WEIGHT_CP}: fibre collision correction weight.
    --> {WEIGHT_NOZ}: redshift failures weight.
    --> {WEIGHT_SYSTOT}: total angular systematic weight.
    --> {WEIGHT_FKP}: FKP weight.

Random catalogues, containing 40 times the number of galaxies of an individual catalogue, are also provided.
Note that in randoms, the NZ values are not calculated with the number of random galaxies, but it coincides with the NZ of the dat files. The WEIGHT_FKP is calculated based on this NZ.