A Foreground Cleaned CMB Map from Non-Gaussianity Measurement
  In this paper we present a new method to estimate a foreground cleaned Cosmic
Microwave Background (CMB) map at a resolution of $1^\circ$ by minimizing the
non-Gaussian properties of the cleaned map which arise dominantly due to
diffuse foreground emission components from the Milky Way. We employ simple
kurtosis statistic as the measure of non-Gaussian properties and perform a
linear combination of 5 frequency maps provided by Wilkinson Microwave
Anisotropy Probe (WMAP) in its 7 year data release in such a way that the
cleaned map has a minimum kurtosis which leads to a non-Gaussianity minimized,
foreground cleaned CMB map. We validate the method by performing Monte-Carlo
simulations. To minimize any residual foreground contamination from the cleaned
map we flag out region near the galactic plane based upon results from
simulations. Outside the masked region our new estimate of CMB map matches well
with the WMAP's ILC map. A simple pseudo-$C_l$ based CMB TT power spectrum
derived from the non-gaussianity minimized map reproduces the earlier results
of WMAP's power spectrum. {\it An important advantage of the method is that it
does not introduce any negative bias in angular power spectrum in low multipole
regime, unlike usual ILC method.} Comparing our results with the previously
published results we argue that CMB results are robust with respect to specific
foreground removal algorithms employed.
