Power asymmetry in CMB polarization maps from PLANCK : a local variance
  analysis
  A persistent signal of power asymmetry on opposite hemispheres of CMB sky was
seen in full-sky temperature measurements made so far. This asymmetry was seen
in microwave sky from WMAP as well as PLANCK satellites, and calls for
attention the larger question of \emph{statistical isotropy}, one of the
foundational principles of modern cosmology. In this work we present an
analysis of polarized CMB maps from PLANCK 2015 full mission data. We apply the
local variance estimator on low resolution $E-$mode maps from PLANCK 2015
polarization \texttt{Commander} solution. We find a significant hemispherical
power asymmetry in polarization data on large angular scales, at the level of
$\sim 2.6-3.9\%$ depending on the galactic mask, and the circular disc radius
used for computing local variance maps. However the direction is found to be
pointing broadly towards CMB kinetic dipole direction. Precise measurements of
CMB polarization in future will shed light on this apparent discrepancy in the
anisotropy axis seen in temperature and polarized CMB sky, and likely influence
of systematics on our findings.
