Cosmological constraints from the CFHTLenS shear measurements using a
  new, accurate and flexible way of predicting nonlinear mass clustering
  We explore the cosmological constraints from cosmic shear using a new way of
modelling the non-linear matter correlation functions. The new formalism
extends the method of Angulo & White (2010), which manipulates outputs of
$N$-body simulations to represent the three-dimensional nonlinear mass
distribution in different cosmological scenarios. We show that predictions from
our approach for shear two-point correlations at $1$ to $300$ arcmin
separations are accurate at the $\sim10$\% level, even for extreme changes in
cosmology. For moderate changes, with target cosmologies similar to that
preferred by analyses of recent Planck data, the accuracy is close to
$\sim5$\%. We combine this approach with a MonteCarlo Markov Chain sampler to
explore constraints on a $\Lambda$CDM model from the shear correlation
functions measured in the Canada-France Hawaii Telescope Lensing Survey
(CFHTLenS). We obtain constraints on the parameter combination $\sigma_8
(\Omega_m/0.27)^{0.6} = 0.801 \pm 0.028$. Combined with results from CMB data,
we obtain marginalised constraints on $\sigma_8 = 0.81 \pm 0.01$ and $\Omega_m
= 0.29 \pm 0.01$. These results are fully compatible with previous analyses,
which supports the validity of our approach. We discuss the advantages of our
method and the potential it offers, including a path to incorporate in detail
the effects of baryons, among others effects, in future high-precision
cosmological analyses.
