Analysis of Polarized Dust Emission Using Data from the First Flight of SPIDER

Understand

Using data from the first flight of SPIDER and from Planck HFI, we probe the properties of polarized emission from interstellar dust in the SPIDER observing region.

• Component separation algorithms operating in both the spatial and harmonic domains are applied to probe their consistency and to quantify modeling errors associated with their assumptions.
• Analyses of diffuse Galactic dust emission spanning the full SPIDER region demonstrate i) a spectral energy distribution that is broadly consistent with a modified-blackbody (MBB) model with a spectral index of $\beta_\mathrm{d}=1.45\pm0.05$ $(1.47\pm0.06)$ for $E$ ($B$)-mode polarization, slightly lower than that reported by Planck for the full sky; ii) an angular power spectrum broadly consistent with a power law; and iii) no significant detection of line-of-sight polarization decorrelation.
• Tests of several modeling uncertainties find only a modest impact (~10% in $\sigma_r$) on SPIDER's sensitivity to the cosmological tensor-to-scalar ratio.