Precision cosmology with a wide area XMM cluster survey
  We explore the cosmological constraints expected from wide area XMM-type
cluster surveys covering 50-200 deg2, under realistic observing conditions. We
perform a Fisher matrix analysis based on cluster number counts in combination
with estimates of the 2-point cluster correlation function. The effect of the
survey design is implemented through an observationally well tested cluster
selection function. Special attention is given to the modelling of the shot
noise and sample variance, which we estimate by applying our selection function
to numerically simulated surveys. We then infer the constraints on the equation
of state of the dark energy considering various survey configurations. We
quantitatively investigate the respective impact of the cluster mass
measurements, of the correlation function and of the 1<z<2 cluster population.
We show that, with some 20 Ms XMM observing time, it is possible to constrain
the dark energy parameters at a level which is comparable to that expected from
the next generation of cosmic probes. Such a survey has also the power to
provide unique insights into the physics of high redshift clusters and AGN
properties.
