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arXiv · 2202.13766

On the Orbital Velocity of Isolated Galaxy Pairs: II Accurate MOND Predictions

Riccardo Scarpa·Renato Falomo·Aldo Treves
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Abstract

Examining a catalogue of isolated galaxy pairs, a preferred orbital intervelocity of ~150 km/s was recently reported. This discovery is difficult to reconcile with the expectations from Newtonian numerical simulations of cosmological structure formations. In a previous paper we have shown that a preferred intervelocity for galaxy pairs is expected in Modified Newtonian Dynamics (MOND). Here a detailed analysis of the MOND predictions is presented, showing that a remarkable agreement with the observations can be achieved for a mass to light ratio M/L~1 in solar units. This agrees with the expectations for a typical stellar population, without requiring non-baryonic dark matter for these systems.

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Riccardo Scarpa, Renato Falomo, Aldo Treves. 2022-02-28. On the Orbital Velocity of Isolated Galaxy Pairs: II Accurate MOND Predictions. https://doi.org/10.1093/mnras%2Fstac564

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