MOKA: a new tool for Strong Lensing Studies
  Strong gravitational lensing is a powerful tool for probing the matter
distribution in the cores of massive dark matter haloes. Recent and ongoing
analyses of galaxy cluster surveys (MACS, CFHTLS, SDSS, SGAS, CLASH, LoCuSS)
have adressed the question of the nature of the dark matter distribution in
clusters. N-body simulations of cold dark-matter haloes consistently find that
haloes should be characterized by a concentration-mass relation that decreases
monotonically with halo mass, and populated by a large amount of substructures,
representing the cores of accreted progenitor halos. It is important for our
understanding of dark matter to test these predictions. We present MOKA, a new
algorithm for simulating the gravitational lensing signal from cluster-sized
haloes. It implements the most recent results from numerical simulations to
create realistic cluster-scale lenses with properties independent of numerical
resolution. We perform systematic studies of the strong lensing cross section
as a function of halo structures. We find that the strong lensing cross
sections depend most strongly on the concentration and on the inner slope of
the density profile of a halo, followed in order of importance by halo
triaxiality and the presence of a bright central galaxy.
