Contamination of the Epoch of Reionization power spectrum in the
  presence of foregrounds
  We construct foreground simulations comprising spatially correlated
extragalactic and diffuse Galactic emission components and calculate the
`intrinsic' (instrument-free) two-dimensional spatial power spectrum and the
cylindrically and spherically averaged three-dimensional k-space power spectra
of the Epoch of Reionization (EoR) and our foreground simulations using a
Bayesian power spectral estimation framework. This leads us to identify a model
dependent region of optimal signal estimation for our foreground and EoR
models, within which the spatial power in the EoR signal relative to
foregrounds is maximised. We identify a target field dependent region, in
k-space, of intrinsic foreground power spectral contamination at low k_perp and
k_parallel and a transition to a relatively foreground-free intrinsic EoR
window in the complement to this region. The contaminated region of k-space
demonstrates that simultaneous estimation of the EoR and foregrounds is
important for obtaining statistically robust estimates of the EoR power
spectrum; biased results will be obtained from methodologies that ignore their
covariance. Using simulated observations with frequency dependent uv-coverage
and primary beam, with the former derived for HERA in 37-antenna and
331-antenna configuration, we recover instrumental power spectra consistent
with their intrinsic counterparts. We discuss the implications of these results
for optimal strategies for unbiased estimation of the EoR power spectrum.
