Origin of the Milky Way disk of satellites: collision of two disk galaxies

Omar Alfonso Bohorquez, Rigoberto Casas Miranda


The dwarf satellite galaxies of the Milky Way are structures that are distributed around the galaxy in an anisotropic manner on a structure called VPOS or DoS. This structure does not match the predictions made by the cold dark matter cosmological model. This model predicts a fully isotropic distribution around the Milky Way. To explain the spatial distribution of the satellite several models have been raised. One of which raises the possibility that these galaxies and their spatial distribution were generated by the collision of two disk galaxies several billion years ago. This paper shows N-body performed with Gadget-2 to determine through their results if it is possible that this event occurred in this way. An analysis for different mass ratios between the incident galaxy, called ghost galaxy, and the host galaxy or target galaxy is performed. Finally a cluster analysis on the remaining collision is performed to determine the spatial distribution of the satellites.


Local Group Dwarf Galaxy, Galaxy disk, Dark Matter, DoS, VPOS

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