Spatial and orbital planes of the Milky Way satellites: unusual but consistent with ΛCDM

Khanh Pham, Andrey Kravtsov, Viraj Manwadkar

Submitted on 6 September 2022


We examine the spatial distribution and orbital pole correlations of satellites in a suite of zoom-in high-resolution dissipationless simulations of Miky Way (MW) sized haloes. We use the measured distribution to estimate the incidence of satellite configurations as flattened and as correlated in their orbital pole distribution as satellite system of the Milky Way. We confirm that this incidence is sensitive to the radial distribution of subhaloes and thereby to the processes that affect it, such as artificial disruption due to numerical effects and disruption due to the central disk. Controlling for the resolution effects and bracketing the effects of the disk, we find that the MW satellite system is somewhat unusual (at the 23σ level) but is statistically consistent with the ΛCDM model, in general agreement with results and conclusions of other recent studies.


Comment: 10 pages, 7 figures, submitted to MNRAS

Subject: Astrophysics - Astrophysics of Galaxies