These data are for collaborators only.

Halo angular momentum data

This directory contains simulated weak lensing convergence maps made from an N-body simulation using the Born approximation. In addition we have catalogs of halos within the field of view and their angular momenta.

The cosmological model simulated was of the LCDM variety with OmegaM=0.3, OmegaL=0.7, h=0.7, n=1.0 and sigma8=0.8. The simulation box was a periodic cube of side length 300Mpc/h (comoving) and 512^3 particles were employed for a particle mass of 1.7e10Msun/h. The force smoothing was 20kpc/h. The underlying simulation is described in more detail in this paper.

Basic data

The basic data consists of a series of 10 convergence (kappa) maps. All of the maps are in FITS format and contain kappa for 5x5 degree fields of view with 2048x2048 pixels. The sources all lie at a single comoving distance of 2400Mpc/h, or z~1.05.

For each map we have catalogs of halos which live in the light cone, along with the angular momenta of the halos. Halos are defined using the friends-of-friends (FoF) procedure with a linking length of 0.15 times the mean interparticle spacing. The halo catalogs are gzipped ascii text files containing one line per halo. The first two columns give the x and y coordinates of the halo, in pixels, then the comoving distance from the observer (Mpc/h), the halo FoF mass (in Msun/h), 1D dark matter velocity dispersion (km/s), and 3 components of the angular momentum (Msun/h Mpc/h km/s). The angular momenta are computed using physical distances wrt the center of mass and peculiar velocities, again with respect to the center of mass.

The "location" of the halo is a somewhat fuzzy concept. I have chosen to use the location of the most bound particle, which also closely corresponds to the position of the densest particle in most of the halos. This seems to work better than the COM of the halo, which can be off by quite a bit from the peak in the kappa maps.

Index of Intrinsic

NameSize (MB)Last modified
cat_01.dat.gz 92005/11/02
cat_02.dat.gz 92005/11/02
kappa_01.fits 162005/11/02
kappa_02.fits 162005/11/02

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Last modified Wed Nov 2 22:58:14 2005