Reproducing galactic rotation curves with a two-component bosonic dark matter model

TL;DR

This paper investigates a two-component bosonic dark matter model, combining scalar and vector bosons, to better reproduce galactic rotation curves and address the dark matter distribution in galaxies.

Contribution

It introduces a novel two-component bosonic dark matter framework that improves the fit to observed galactic rotation curves over previous models.

Findings

Enhanced agreement with observed galaxy rotation curves.

Potential explanation for matter deficits in dwarf and spiral galaxies.

Demonstrates the effectiveness of combining scalar and vector bosonic dark matter components.

Abstract

Bosonic stars,hypothetical astrophysical entities, are generally categorized into two primary classes based on the nature of their constituent particles: Einstein Klein Gordon stars, made up of massive scalar bosons, and Proca stars, their vector ''cousins''. Depending on the boson masses and field frequencies, these objects may exhibit properties of diffuse, massive structures, with sizes comparable to or even exceeding those of galaxies. This concept has inspired the bosonic dark matter halo hypothesis, providing a theoretical framework to effectively model the dark matter content of galactic halos. In this paper we build on our previous work to explore the possibility of using vector and scalar bosons to model the components of galactic dark matter halos and subhalos in order to reproduce the observed rotation curves of galaxies. By employing diverse combinations of those bosonic dark matter models in conjunction with observable data for a sample of galaxies, we show that our two component dark matter approach notably improves the agreement between observations and theoretical predictions with respect to our previous investigation. Our framework may shed new light on the enduring mystery surrounding the apparent matter deficit observed in dwarf and spiral galaxies.