Statistical properties of galactic CMB foregrounds: dust and synchrotron
  Recent Planck observations have revealed some of the important statistical
properties of synchrotron and dust polarisation, namely, the $B$ to $E$ mode
power and temperature-$E$ (TE) mode cross-correlation. In this paper, we extend
our analysis in Kandel et al. (2017) that studied $B$ to $E$ mode power ratio
for polarised dust emission to include TE cross-correlation and develop an
analogous formalism for synchrotron signal, all using a realistic model of
magnetohydrodynamical (MHD) turbulence. Our results suggest that the Planck
results for both synchrotron and dust polarisation can be understood if the
turbulence in the Galaxy is sufficiently sub-Alfv\'enic. We also show how $B$
to $E$ ratio as well as the TE cross-correlation can be used to study media
magnetisation, compressibility, and level of density-magnetic field
correlation.
