Speaker
Description
Satellite galaxies tend to occupy the region in between pairs of massive galaxies, as seen in both the Local Group (between the Milky Way and M31) and distant galaxy pairs in SDSS. Possible origins include local gravity between paired halos and the large-scale filamentary environment. We investigate the anisotropic distribution of satellites around pairs of galaxy groups in SDSS/DR7 as well as pairs of dark matter halos in the ELUCID simulation. We construct mock catalogs based on the TNG300 hydrodynamic simulation to make a direct comparison between our observational and simulation results. The results from both the mock catalogs and the simulation agree quite well with SDSS. Our results and tests on the mocks suggest that the anisotropic distribution of satellites around paired halos can be naturally explained by the alignment of the galaxy distribution within dark halos with large-scale filamentary structures, rather than the local gravity as proposed by previous studies.
