Detalles de publicación

PP 024124

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

Martín López-Corredoira (1,2)
(1) IAC; (2) ULL
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<22 kpc, |z|<3 kpc.

Our conclusions are as follows: (i) the model of the spherical dark matter halos and the MOND model are compatible with the data; (ii) the model of the disky dark matter (with density proportional to the gas density) is excluded; (iii) the total lack of dark matter (there is only visible matter) within Newtonian gravity is compatible with the data; for instance, at solar Galactocentric radius, we obtained Σ=39±18 M⊙ pc^{−2} for z=1.05 kpc, compatible with the expected value for visible matter alone of 44 M⊙ pc^{−2}, thus allowing zero dark matter. Similarly, for R>R⊙, z=1.05 kpc: Σ=28.7±9.6, 23.0±5.7, 16.9±5.8, 11.4±6.6 M⊙ 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.

 
Aceptado para publicación en ApJ | Enviado el 2024-12-18 | Proyecto P/309403