Study of Various Dark Matter Halo Profiles in Milky Way and M31 Galaxies within the Standard Cosmology Framework

Abstract

In this paper, we study the rotation curves of the Milky Way galaxy (MW) and Andromeda galaxy (M31) by considering their bulge, disk, and halo components. We model the bulge region by the widely accepted de Vaucouleur's law and the disk region by the well-established exponential profile. In order to understand the distribution of dark matter in the halo region, we consider three different dark matter profiles in the framework of the standard $\Lambda$CDM model, namely, Navarro-Frenk-White (NFW), Hernquist, and Einasto profiles. We use recent datasets of rotation curves of the Milky Way and Andromeda galaxies. The data consist of rotation velocities of the stars and gas in the galaxy as a function of the radial distance from the center. Using Bayesian statistics, we perform an overall fit including all the components, i.e., bulge, disk, and halo, with the data. Our results indicate that the NFW and Hernquist profiles are in concordance with the observational data points. However, the Einasto profile poorly explains the behavior of dark matter in both the galaxies.

arXiv comment16 pages, 8 figures, and 2 tables. Accepted for publication in Res. Astron. Astrophys

References in corpus (20)

• emcee: The MCMC Hammer
• A Universal Density Profile from Hierarchical Clustering
• The Structure of Cold Dark Matter Halos
• The Structure of Dark Matter Haloes in Dwarf Galaxies
• The Inner Structure of LambdaCDM Halos III: Universality and Asymptotic Slopes
• Analytical Models For Galactic Nuclei
• Empirical models for Dark Matter Halos. I. Nonparametric Construction of Density Profiles and Comparison with Parametric Models
• The Extended Rotation Curve and the Dark Matter Halo of M33
• The Milky Way's rotation curve out to 100 kpc and its constraint on the Galactic mass distribution
• Rotation Curve and Mass Distribution in the Galactic Center --- From Black Hole to Entire Galaxy ---
• A wide-field HI mosaic of Messier 31. II.The disk warp, rotation and the dark matter halo
• Rotation Curve of the Milky Way out to $\sim$ 200 kpc
• Extended HI Rotation Curve and Mass Distribution of M31
• Dark Halos of M31 and the Milky Way
• Improved Modeling of the Mass Distribution of Disk Galaxies by the Einasto Halo Model
• The Dark Matter Profiles in the Milky Way
• Rotation and Mass in the Milky Way and Spiral Galaxies
• Einstein, Planck and Vera Rubin: relevant encounters between the Cosmological and the Quantum Worlds
• Fitting functions for dark matter density profiles
• Milky Way and M31 rotation curves: $\Lambda$CDM vs. MOND

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