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arXiv · 2104.12787

The lopsided distribution of satellites of isolated central galaxies

Peng Wang·Noam I. Libeskind·Marcel S. Pawlowski·Xi Kang·Wei Wang·Quan Guo·Elmo Tempel
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Abstract

Satellites are not randomly distributed around their central galaxies but show polar and planar structures. In this paper, we investigate the axis-asymmetry or lopsidedness of satellite galaxy distributions around isolated galaxies in a hydrodynamic cosmological simulation. We find a statistically significant lopsided signal by studying the angular distribution of the satellite galaxies' projected positions around isolated central galaxies in a two-dimensional plane. The signal is dependent on galaxy mass, color and large-scale environment. Satellites that inhabit low-mass blue hosts, or located further from the hosts show the most lopsided signal. Galaxy systems with massive neighbors exhibit stronger lopsidedness. This satellite axis-asymmetry signal also decreases as the universe evolves. Our findings are in agreement with recent observational results, and they provide a useful perspective for studying galaxy evolution, especially on the satellite accretion, internal evolution and interaction with the cosmic large-scale structure.

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Peng Wang, Noam I. Libeskind, Marcel S. Pawlowski, Xi Kang, Wei Wang, Quan Guo, Elmo Tempel. 2021-04-26. The lopsided distribution of satellites of isolated central galaxies. https://doi.org/10.3847/1538-4357%2Fabfc4f

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