The Cosmic Radio Dipole and Observer Effects in SKA all-sky surveys
Abstract
The Square Kilometre Array (SKA) will observe our Universe on the largest scales and so enable the study of fundamental assumptions in cosmology, such as cosmic homogeneity and isotropy. Observations over recent years have reaffirmed an unexpected challenge to the Cosmological Principle first seen in measurements of the cosmic radio dipole. This dipole anisotropy is thought to be caused by our local observer motion, however, it is observed to be about three times larger than predicted, with significances exceeding 5σ. The SKA is in a unique position to shed light on this anomaly by measuring this and other effects related to our observer motion. To quantify this, we forecast the capability of large-angle HI and continuum surveys of the SKA to constrain the kinematic matter dipole in galaxy number counts, the modulation of the matter power spectrum by a kinematic dipole, and kinematic spectral distortions of diffuse radio emission.
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BibTeX
@misc{bertacca2026cosmic,
title = {{The Cosmic Radio Dipole and Observer Effects in SKA all-sky surveys}},
author = {D. Bertacca and L. Böhme and B. Bottazzi Baldi and C. Burigana and M. Y. Elkhashab and C. L. Hale and S. von Hausegger and H. R. Klöckner and M. Land-Strykowski and G. F. Lewis and V. Mittal and O. T. Oayda and D. J. Schwarz and P. Tiwari and T. Trombetti and J. D. Wagenveld},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.17022},
eprint = {2610.17022},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.17022},
note = {CC BY-NC-SA 4.0},
}
RIS
TY - UNPB
TI - The Cosmic Radio Dipole and Observer Effects in SKA all-sky surveys
AU - D. Bertacca
AU - L. Böhme
AU - B. Bottazzi Baldi
AU - C. Burigana
AU - M. Y. Elkhashab
AU - C. L. Hale
AU - S. von Hausegger
AU - H. R. Klöckner
AU - M. Land-Strykowski
AU - G. F. Lewis
AU - V. Mittal
AU - O. T. Oayda
AU - D. J. Schwarz
AU - P. Tiwari
AU - T. Trombetti
AU - J. D. Wagenveld
PY - 2026
DA - 2026/10/12
PB - arXiv
DO - 10.48550/arxiv.2610.17022
UR - https://arxiv.org/abs/2610.17022
AB - The Square Kilometre Array (SKA) will observe our Universe on the largest scales and so enable the study of fundamental assumptions in cosmology, such as cosmic homogeneity and isotropy. Observations over recent years have reaffirmed an unexpected challenge to the Cosmological Principle first seen in measurements of the cosmic radio dipole. This dipole anisotropy is thought to be caused by our local observer motion, however, it is observed to be about three times larger than predicted, with significances exceeding 5σ. The SKA is in a unique position to shed light on this anomaly by measuring this and other effects related to our observer motion. To quantify this, we forecast the capability of large-angle HI and continuum surveys of the SKA to constrain the kinematic matter dipole in galaxy number counts, the modulation of the matter power spectrum by a kinematic dipole, and kinematic spectral distortions of diffuse radio emission.
ER -