ADDGALS: Adding Density Determined Galaxies to Lightcone Simulations

The Buzzard Flock employs a method for creating simulated galaxy catalogs that accurately reproduces galaxy luminosities, colors, and clustering over large cosmic volumes. The technique, called ADDGALS (Adding Density Dependent GAlaxies to Lightcone Simulations), uses an empirical method to embed galaxies within lightcone outputs of cosmological simulations. It can be applied to lower-resolution simulations than are possible with commonly used methods, such as halo occupation distributions, subhalo abundance matching, and semi-analytic models, while still accurately reproducing projected galaxy clustering statistics down to scales of 100 h^-1kpc. A methods paper describing this algorithm will be on the arxiv soon!

CALCLENS: Curved-sky grAvitational Lensing for Cosmological Light conE simulatioNS

Weak lensing statistics in our simlations are computed using CALCLENS, an algorithm for efficiently computing weak gravitational lensing shear signals from large N-body light cone simulations over a curved sky. This algorithm properly accounts for the sky curvature and boundary conditions, is able to produce redshift-dependent shear signals including corrections to the Born approximation by using multiple-plane ray tracing, and properly computes the lensed images of source galaxies in the light cone.