The Density Distribution of Dark Matter in the Milky Way Based on Stellar Velocities Measured by GAIA DR2
Main Article Content
Keywords
galaxies, dark matter, milky way, rotation curve, dark matter density
Abstract
Since the early stages of the formation of the universe, dark matter has played a crucial role in mapping the large scale structures, being the frame of matter overdensities which grew up to form galactic and intergalactic structures. However, due to its mysterious nature and the property only interacting with gravitational fields, not much light is shed on the discovery and understanding of dark matter’s possible particle nature. This paper aims to interpret the density distribution of dark matter in different regions of the Milky Way(Bulge, Disk, Halo) from most recent models(NFW, Einasto, Isothermal, Burkert, Moore) and match it with the data of stellar rotational velocities measured by GAIA DR2 database. We do not directly derive velocities from raw GAIA DR2, but instead use compiled rotation curve data calibrated with GAIA measurements taken from Sofue et al. 2025[20]. We have also extrapolated parameters and normalization factors regarding each model, and evaluated with a more rudimentary method offered from Cirelli, M. et al. 2011[7]. Through our method, we provide a rudimentary overview on how the dark matter density profiles correlate with the newest DR2 data and evaluate their applicability. In turn, we hope the results offer insight on which model could be compatible concurrently in our galaxy.
References
- [1]Baba, J. (2025). Bar-driven Streaming Motions Mimic a Massive Bulge in the Inner Milky Way. [online] arXiv.org. Available at: https://arxiv.org/abs/2507.12702 [Accessed 13 Oct. 2025].
- [2]Balazs, C., Torsten Bringmann, Kahlhoefer, F. and White, M. (2024). A Primer on Dark Matter. Alphaxiv.org. [online] doi:https://doi.org/10.1103/RevModPhys.90.045002.%201605.04909.
- [3]Begeman, K.G., Broeils, A.H. and Sanders, R.H. (1991). Extended Rotation Curves of Spiral galaxies: Dark Haloes and Modified Dynamics. Monthly Notices of the Royal Astronomical Society, 249(3), pp.523–537. doi:https://doi.org/10.1093/mnras/249.3.523.
- [4]Beordo, W., Crosta, M. and Lattanzi, M.G. (2024). Exploring Milky Way rotation curves with Gaia DR3: a comparison between $\Lambda$CDM, MOND, and General Relativistic approaches. [online] arXiv.org. Available at: https://arxiv.org/abs/2407.12482 [Accessed 13 Oct. 2025].
- [5]Burkert, A. (1994). The Structure of Dark Matter Halos in Dwarf Galaxies. The Astrophysical Journal, 447(1). doi:https://doi.org/10.1086/309560.
- [6]Ciotti, L. (1999). Inversion of the Abel Equation for Toroidal Density Distributions. [online] arXiv.org. Available at: https://arxiv.org/abs/astro-ph/9903056 [Accessed 31 Mar. 2026].
- [7]Cirelli, M., Corcella, G., Hektor, A., Hütsi, G., Kadastik, M., Panci, P., Raidal, M., Sala, F. and Strumia, A. (2011). PPPC 4 DM ID: a poor particle physicist cookbook for dark matter indirect detection. Journal of Cosmology and Astroparticle Physics, 2011(03), pp.051–051. doi:https://doi.org/10.1088/1475-7516/2011/03/051.
- [8]Dehnen, W. and Binney, J. (1998). Mass models of the Milky Way. Monthly Notices of the Royal Astronomical Society, [online] 294(3), pp.429–438. doi:https://doi.org/10.1111/j.1365-8711.1998.01282.x.
- [9]Einasto, J. and Einasto, M. (1999). Dark Matter in Groups and Clusters of Galaxies. [online] ar5iv. Available at: https://ar5iv.labs.arxiv.org/html/astro-ph/9909437 [Accessed 31 Mar. 2026].
- [10]G. de Vaucouleurs (1958). Photoelectric Photometry of the Andromeda Nebula in the UBV System. The Astrophysical Journal, 128(465), pp.465–465. doi:https://doi.org/10.1086/146564.
- [11]Kapteyn, J.C. (1922). First Attempt at a Theory of the Arrangement and Motion of the Sidereal System. The Astrophysical Journal, 55, p.302. doi:https://doi.org/10.1086/142670.
- [12]Laurin Söding, Bartel, R.L. and Philipp Mertsch (2025). Local dark matter density from Gaia DR3 K-dwarfs using Gaussian processes. Monthly Notices of the Royal Astronomical Society, [online] 542(4), pp.2987–2997. doi:https://doi.org/10.1093/mnras/staf1391.
- [13]Massey, R., Kitching, T. and Richard, J. (2010). The dark matter of gravitational lensing The dark matter of gravitational lensing 2. [online] Available at: https://arxiv.org/pdf/1001.1739 [Accessed 2 Feb. 2026].
- [14]Moore, B. (1994). Evidence against dissipation-less Dark Matter from Observations of Galaxy Haloes. Nature, [online] 370(6491), pp.629–631. doi:https://doi.org/10.1038/370629a0.
- [15]NASA (2006). Bullet Cluster. [online] Available at: https://chandra.harvard.edu/graphics/resources/handouts/lithos/bullet_lithos.pdf.
- [16]Navarro, J.F. (1996). The Structure of Cold Dark Matter Halos. Symposium - International Astronomical Union, [online] 171(9508025), pp.255–258. doi:https://doi.org/10.1017/s0074180900232452.
- [17]Navarro, J.F., Ludlow, A., Springel, V., Wang, J., Vogelsberger, M., White, S.D.M., Jenkins, A., Frenk, C.S. and Helmi, A. (2009). The diversity and similarity of simulated cold dark matter haloes. Monthly Notices of the Royal Astronomical Society, 402(1), pp.21–34. doi:https://doi.org/10.1111/j.1365-2966.2009.15878.x.
- [18]Navarro, J.F. and White, S. (1993). Simulations of dissipative galaxy formation in hierarchically clustering universes - I: Tests of the code. Monthly Notices of the Royal Astronomical Society, [online] 265(2), pp.271–300. doi:https://doi.org/10.1093/mnras/265.2.271.
- [19]Sofue, Y. (2020). Rotation Curve of the Milky Way and the Dark Matter Density. [online] arXiv.org. Available at: https://arxiv.org/abs/2004.11688 [Accessed 13 Oct. 2025].
- [20]Sofue, Y. and Kohno, M. (2025). The inner rotation curve of the Milky Way. [online] arXiv.org. Available at: https://arxiv.org/abs/2509.23581 [Accessed 13 Oct. 2025].
- [21]Woudenberg, H.C. and Helmi, A. (2024). First measurement of the triaxiality of the inner dark matter halo of the Milky Way. Astronomy & Astrophysics, [online] 691(A&A Volume 691, November 2024 A277), p.A277. doi:https://doi.org/10.1051/0004-6361/202451743.
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