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arXiv · 2412.09665

Milky Way dark matter distribution or MOND test from vertical stellar kinematics with Gaia DR3

Martin Lopez-Corredoira
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Abstract

Vertical stellar kinematics+density can be used to trace the dark matter distribution [or the equivalent phantom mass in a Modified Newtonian Dynamics (MOND) scenario] through Jeans equations. In this paper, we want to improve this type of analysis by making use of the recent data of the 6D information from the Gaia-DR3 survey in the anticenter and the Galactic poles to obtain the dynamical mass distribution near plane regions, including extended kinematics over a wide region of 8 kpc$ R_\odot$, $z=1.05$ kpc: $\Sigma=28.7\pm 9.6$, $23.0\pm 5.7$, $16.9\pm 5.8$, $11.4\pm 6.6$ M$_\odot$ pc$^{-2}$, respectively, for $R=10,13,16,19$ kpc, compatible with visible matter alone. Larger error bars in comparison with previous works are not due to worse data or a more awkward technique but to a stricter modeling of the stellar distribution.

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Martin Lopez-Corredoira. 2024-12-12. Milky Way dark matter distribution or MOND test from vertical stellar kinematics with Gaia DR3. https://arxiv.org/abs/2412.09665

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