The influence of the Zone of Avoidance on the measurement of the clustering dipole of galaxies

Magdalena Krupa, Maciej Bilicki, Agnieszka Pollo

Our own Galaxy obscures a large (approximately 20%) portion of the sky, creating the so-called Zone of Avoidance (ZoA), which poses problems for observations of the extragalactic universe. Because of that, all cosmological measurements based on all-sky statistics of the large scale structure of the Universe need to compensate for the lack of information from the sky areas hidden behind the ZoA. Among such cosmological measurements there are tests of the validity of the Cosmological Principle via calculation of the clustering dipole of galaxies, for which a full sky coverage is absolutely vital. In this paper we review different methods of filling the ZoA and discuss their effectiveness tested on simulated galaxy catalogs. In particular we re-estimate the expected accuracy of recovery of the amplitude and the direction of the estimated acceleration of the Local Group. Finally, we present the results of the clustering dipole measurements in the 2MASS catalog obtained with the best selected method and with a realistic error estimation.

Proceedings of the Polish Astronomical Society, vol. 10, 323-328 (2020)

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