Scalar Field Dark Matter mass model and evolution of rotation curves for Lsb galaxies

TL;DR

This paper investigates the evolution of gas rotation curves in scalar field dark matter models, demonstrating that a cored mass distribution aligns better with observations than cuspy profiles, by incorporating baryonic effects in hydrodynamic simulations.

Contribution

It advances previous static models by including baryonic dynamics and gas evolution, providing more realistic simulations of galaxy rotation curves within the SFDM framework.

Findings

Cored SFDM halos fit observed rotation curves better than cuspy models.

Including baryonic components affects gas velocity and density evolution.

Simulations support the cored profile as a preferable dark matter distribution.

Abstract

We study the evolution of gas rotation curves within the scalar field dark matter (SFDM) model. In this model the galactic haloes are astronomical Bose-Einstein Condensate drops of scalar field. These haloes are characterized by a constant-density core and are consistent with observed rotation curves of dark matter dominated galaxies, a missing feature in CDM haloes resulting from DM-only simulations. We add the baryonic component to the SFDM haloes and simulate the evolution of the dark matter tracer in a set of grid-based hydrodynamic simulations aimed to analyse the evolution of the rotation curves and the gas density distribution in the case of dark matter dominated galaxies. Previous works had found that when considering an exact analytic solution for a static SF configuration, the free parameters of the model allows for good fits to the rotation curves, we confirm that in our simulations but now taking into account the evolution of the baryonic component in a static dark matter and stellar disk potential. Including live gas is a step forward from the previous work using SFDM, as for example, the rotation velocity of the gas is not always exactly equal to the circular velocity of a test particle on a circular orbit. Contrasting with the data the cored mass model presented here is preferred instead of a cuspy one.