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arXiv · 1712.03880

Empirical velocity profiles for galactic rotation curves

E. Lopez Fune
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Abstract

A unified parametrization of the circular velocity, which accurately fits 850 galaxy rotation curves without needing in advance the knowledge of the luminous matter components, nor a fixed dark matter halo model, is proposed. A notable feature is that the associated gravitational potential increases with the distance from the galaxy center, giving rise to a length scale indicating a finite size of a galaxy, and after, the Keplerian fall-off of the parametrized circular velocity is recovered according to Newtonian gravity, making possible the estimation of the total mass enclosed by the galaxy.

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E. Lopez Fune. 2017-12-11. Empirical velocity profiles for galactic rotation curves. https://doi.org/10.1093/mnras%2Fstx3245

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