The Q Continuum Simulation: Harnessing the Power of GPU Accelerated
  Supercomputers
  Modeling large-scale sky survey observations is a key driver for the
continuing development of high resolution, large-volume, cosmological
simulations. We report the first results from the 'Q Continuum' cosmological
N-body simulation run carried out on the GPU-accelerated supercomputer Titan.
The simulation encompasses a volume of (1300 Mpc)^3 and evolves more than half
a trillion particles, leading to a particle mass resolution of ~1.5 X 10^8
M_sun. At this mass resolution, the Q Continuum run is currently the largest
cosmology simulation available. It enables the construction of detailed
synthetic sky catalogs, encompassing different modeling methodologies,
including semi-analytic modeling and sub-halo abundance matching in a large,
cosmological volume. Here we describe the simulation and outputs in detail and
present first results for a range of cosmological statistics, such as mass
power spectra, halo mass functions, and halo mass-concentration relations for
different epochs. We also provide details on challenges connected to running a
simulation on almost 90% of Titan, one of the fastest supercomputers in the
world, including our usage of Titan's GPU accelerators.
