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arXiv · 2112.03637

On the Orbital Velocity of Isolated Galaxy Pairs: a test of gravity in the low acceleration regime

Riccardo Scarpa·Renato Falomo·Aldo Treves
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Abstract

The dynamics of isolated galaxy pairs represents an important tool to investigate the behavior of gravity in the low acceleration regime. Statistical analysis of a large sample of galaxy pairs led to the noticeable discovery of a region of preferred 3-dimensional velocities centered at $\sim 150$ km/s and $\sim 100$ km/s wide, a feature hard to justify in the context of numerical simulations of cosmological structure formation. It is shown here that such a feature is expected within the framework of the Modified Newtonian Dynamics, which, however, predicts it to be centered at $\sim$ 170 Km/s.

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Riccardo Scarpa, Renato Falomo, Aldo Treves. 2021-12-07. On the Orbital Velocity of Isolated Galaxy Pairs: a test of gravity in the low acceleration regime. https://doi.org/10.1093/mnras%2Fstab3636

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