SZ Halo Catalog

Cosmological parameters are based closely on the five year WMAP data release.

nsinit  = 0.96
hubble0 = 0.71
wde     = -1.0
sigma8  = 0.80
omegam  = 0.264
omegal  = 0.736 = 1-omegam
omegab  = 0.044
YHe     = 0.24
XH      = 0.76
Tcmb    = 2.726

The TPM N-body code was run with 1024^3 particles in a 1000 Mpc/h box. Halos were identified using a 
friends-of-friends algorithm and those belonging to a light cone spanning an octant for redshifts 0 < z < 3 have 
been saved.

TPM N-body simulation
L  = 1000 Mpc/h
Np = 1024^3
mp = 6.82E10 Msolar/h = 9.61E10 Msolar

FoF halo finder
bfof  = 0.2 times mean interparticle spacing
Nmin  = 293 particles
Mmin  = 2.00E13 Msolar/h = 2.82E13 Msolar
Nhalo = 1414339

SZ maps are available as binary FITS files with the minimum header. Maps are in Healpix format with Nside = 8192 
and Npix = 12*Nside^2. Full sky maps are constructed by replicating the octant as follow:

Northern hemisphere
theta_N = theta_O
phi_N   = phi_O + n*pi/2 where n = 0,1,2,3

Southern hemisphere
theta_S = pi - theta_N
phi_S   = 2*pi - phi_N

Sky_sz_nu.fits are distortion maps, in units of Delta T/T, at various GHz frequencies. These maps are for the 
redshift range 0 < z < 10. They include relativistic corrections.

Sky_tsz.fits and Sky_ksz.fits are the Compton y and Doppler b maps, respectively. These maps are for the same 
redshift range, but do not include relativistic corrections.


SZ halo catalogs are available in ascii and binary formats. There are 1414339 halos in the first octant for 
redshifts 0 < z < 3. For each halo, there are 48 numbers as described below.

Here is a sample codelet to read in the binary data file

  integer(4), parameter           :: nhalo = 1414339
  real(4),    dimension(48,nhalo) :: halo

  do i=1,nhalo
    read(1) halo(:,i)

Halo array
halo(    1,i) = redshift
halo(    2,i) = ra  in degrees
halo(    3,i) = dec in degrees
halo(  4:6,i) = comoving position of halo potential minimum in Mpc
halo(  7:9,i) = proper peculiar velocity in km/s
halo(   10,i) = Mfof in Msolar

halo(   11,i) = Mvir     in Msolar
halo(   12,i) = Mgas_vir in Msolar
halo(   13,i) = Rvir     in proper Mpc
halo(   14,i) = Integrated TSZ within Rvir in arcminute^2
halo(   15,i) = Integrated KSZ within Rvir in arcminute^2
halo(16:21,i) = Integrated SZ at 148,219,277,30,90,350 GHz

halo(22:32,i) = Same as 11-21 but for within R200
halo(33:43,i) = Same as 11-21 but for within R500

halo(   44,i) = Mstar               in Msolar
halo(   45,i) = central gas density in Msolar/Mpc^3
halo(   46,i) = central temperature in keV
halo(   47,i) = central pressure    in Msolar/Mpc/Gyr^2
halo(   48,i) = central potential   in (Mpc/Gyr)^2

Simulation Overview Page

A service of the HEASARC and of the Astrophysics Science Division at NASA/GSFC
Goddard Space Flight Center, National Aeronautics and Space Administration
HEASARC Director: Dr. Alan P. Smale
LAMBDA Director: Dr. Eric R. Switzer
NASA Official: Dr. Eric R. Switzer
Web Curator: Mr. Michael R. Greason