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arXiv · 2105.08658

Ring of attraction: overlapping directions of the dipole modulation of the CMB, the parity asymmetry, and kinematic dipole percolation zone

James Creswell·Pavel Naselsky
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Abstract

The largest anisotropy in the cosmic microwave background (CMB) is the 3 mK kinematic dipole reflecting our motion with respect to the CMB frame and pointed in the direction $(l, b) = (264^\circ, +48^\circ)$ in Galactic coordinates. We introduce the concept of the ring of attraction (RA), which is orthogonal to the axis of the kinematic dipole. These directions overlap with the zone of percolation for the kinematic dipole, where its amplitude almost vanishes. We show that along this ring are oriented the directions of the dipole modulation of the CMB, and positions of the peaks responsible for generation of parity asymmetry. This coincidence is peculiar at around the 3 sigma level. We analyzed the "interaction" of low multipoles of the CMB with RA and showed that for odd modes there is a sequence of peaks in the RA direction. These peaks correlate with each other for different multipoles and result in mutual amplification of the odd $\ell$ signal for the first 30 multipoles. Our method sheds new light on the nature of parity asymmetry. It consists of the deficit of symmetrically located and equal in amplitude peaks in the CMB map in comparison with asymmetric peaks.

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James Creswell, Pavel Naselsky. 2021-05-18. Ring of attraction: overlapping directions of the dipole modulation of the CMB, the parity asymmetry, and kinematic dipole percolation zone. https://arxiv.org/abs/2105.08658

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