Improved galactic foreground removal for B-mode detection with clustering methods

ABSTRACT Characterizing the sub-mm Galactic emission has become increasingly critical especially in identifying and removing its polarized contribution from one emitted by cosmic microwave background (CMB). In this work, we present a parametric foreground removal performed on to sub-patches identified celestial sphere means of spectral clustering. Our approach takes into account efficiently both geometrical affinity similarity induced measurements accompanying errors. The optimal partition is then used parametrically separate encoding thermal dust synchrotron CMB applied two nominal observations forthcoming experiments ground space. Moreover, clustering tracers that are different data for component separation, e.g. index maps synchrotron. Performing fit singularly each derived regions results an overall improvement: controlling bias uncertainties B-mode recovered maps. We finally apply technique using map number clouds along line sight, $\mathcal {N}_c$, as estimated H i perform fitting patches map. show adopting {N}_c$ tracer related emission, reducing residuals post-component separation. code made publicly available https://github.com/giuspugl/fgcluster.