A novel CMB polarization likelihood package for large angular scales built from combined WMAP and

We present a cosmic microwave background (CMB) large-scale polarization dataset obtained by combining Wilkinson Microwave Anisotropy Probe (WMAP) in the K, Q, and V bands with the Planck 70 GHz maps. We employed the legacy frequency maps released by the WMAP and Planck collaborations and performed our own Galactic foreground mitigation technique, relying on Planck 353 GHz for polarized dust and on Planck 30 GHz and WMAP K for polarized synchrotron. We derived a single, optimally noise-weighted, low residual foreground map and the accompanying noise covariance matrix. These are shown through χ2 analysis to be robust over an ample collection of Galactic masks. We used this dataset, along with the Planck legacy Commande