============== select1000.gz ==================
select1000: 0.1% dark matter particles (boxsize, 500Mpc/h)
data format:
column 1, x (Mpc/h)
column 2, y (Mpc/h)
column 3, z (Mpc/h)


=============== subhalos.tar.gz ================
subhalo_100.txt: subhalo catalog at redshift z=0, 48846170 subhalos.
data format:
col 1: subhalo ID (from 1 to 48846170)
col 2: subhalo mass (10^10 M_sun/h)
col 3: position x (Mpc/h)
col 4: position y
col 5: position z
col 6: velocity x (km/s)
col 7: velocity y
col 8: velocity z
col 9:  Angular Momentum x (specific AM; unit: Mpc/h * km/s)
col 10: angular momentum y
col 11: angular momentum z
col 12: velocity dispertion  (km/s)
col 13: velocity Vmax
col 14: spin parameter lambda 
col 15: half mass radius


------ age_z.txt ------
data format:
col 1: subhalo ID (from 1 to 48846170)
col 2: z_formation formation time (redshift z)
col 3: M_peak, peak mass 
col 4: redshift at peak mass
col 5: peak Vmax
col 6: redshift at peak Vmax
col 7: M_acc accretion mass  (for central subhalo, M_acc = 0)
col 8: z_acc redshift at accretion
col 9: Vmax_acc at accretion 

Note:
a: we set z_formation = -1 if no progenitor have mass less than M_peak/2 
(e.g. subhalos at z~0 with particle number ~ 20)
b: For central subhalos, we set M_acc = z_acc = Vmax_acc = -1. 


------ Mass_Rvir_Cvir.txt: ------
data format:
col 1: subhalo ID (from 1 to 48846170)
col 2: flag  (flag = 1, central ; flag =2, satellite)
col 3: Subhalo Mass (unit: 10^10 M_sun/h, PaiticleMass*SubLength )
col 4: M_vir (10^10 M_sun/h)
col 5: R_vir (Mpc/h)
col 6: C_vir, virial concentration

Note: 
a: IF flag = 2, then we set M_vir=R_vir=C_vir=0
b:  M_vir, R_vir, C_vir are calculated from the host halo 
in which the main subhalo reside.

------ host_id1.txt: ------ 
data format
col 1: subhalo ID (from 1 to 48846170)
col 2: host FOF halo ID (from 1 to 48129323)
col 3: central or satelite (1: central;  2:satellite)


=============== hosthalos.tar.gz ================
halo_100.txt: halo catalog at redshift z=0, 48129323 halos.
data format:
col 1: halo mass (unit: 10^10 M_sun/h, particle mass: 0.30875*10^10 M_sun/h)
col 2-4: halo positon (Mpc/h, comoving distance)
col 5-7: halo velocity  (km/s)
col 8: velocity dispersion (km/s)