http://arxiv.org/abs/2208.07382
We present evidence for scale-independent misalignment of interstellar dust filaments and magnetic fields. We estimate the misalignment by comparing millimeter-wave dust-polarization measurements from Planck with filamentary structures identified in neutral-hydrogen (HI) measurements from HI4PI. We find that the misalignment angle displays a scale independence (harmonic coherence) for features larger than the HI4PI beam width ($16.2’$). We additionally find a spatial coherence on angular scales of $\mathcal{O}(1^\circ)$. We present several misalignment estimators formed from the auto- and cross-spectra of dust-polarization and HI-based maps, and we also introduce a map-space estimator. Applied to large regions of the high-Galactic-latitude sky, we find a global misalignment angle of $\sim 2^\circ$, which is robust to a variety of masking choices. By dividing the sky into small regions, we show that the misalignment angle correlates with the parity-violating $TB$ cross-spectrum measured in the Planck dust maps. The misalignment paradigm also predicts a dust $EB$ signal, which is of relevance in the search for cosmic birefringence but as yet undetected; the measurements of $EB$ are noisier than of $TB$, and our correlations of $EB$ with misalignment angle are found to be weaker and less robust to masking choices.
A. Cukierman, S. Clark and G. Halal
Wed, 17 Aug 22
58/58
Comments: 30 pages, 17 figures
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