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arXiv · 2608.19039

Dipolar power asymmetry in wide-angle correlations of galaxy density, velocity and ellipticity

Yusuke Mikura·Teppei Okumura·Ippei Obata·Maresuke Shiraishi
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Abstract

The large-scale structure of the universe has the potential to probe anomalies suggested by observations of the cosmic microwave background. In this work, we focus on a position-dependent dipolar modulation of the primordial power spectrum and develop a full-sky formalism for computing correlation functions of galaxy density, velocity and ellipticity. By comparing the correlation functions obtained with and without the plane-parallel approximation, we show that wide-angle corrections become non-negligible for opening angles $\Theta \gtrsim 30^\circ$. Our results demonstrate that wide-angle corrections must be taken into account when testing the dipolar modulation with future large-scale structure surveys.

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Yusuke Mikura, Teppei Okumura, Ippei Obata, Maresuke Shiraishi. 2026-08-19. Dipolar power asymmetry in wide-angle correlations of galaxy density, velocity and ellipticity. https://arxiv.org/abs/2608.19039

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