The structure of accreted stellar streams

Many of the Milky Way's globular clusters are likely accreted from satellite galaxies that have long since merged with Way. When these susceptible to tidal disruption, this process starts already inside parent leading an early stellar stream within satellite. merges Way, cluster and its pre-merger in a somewhat chaotic process. Here, we investigate properties after merger as would see it today using suite simulations accretion events. We find leads wide range behaviors, but generally scatters over wide, two-dimensional area sky. The behavior ranges set few or more well-defined "sub-streams" extending out post-merger thin by tens degrees, widely dispersed debris much sky, depending on how close center MilkyWay happened. Using mock Gaia-like observations simulated streams, demonstrate accreted-stream component can explain off-track features observed GD-1 stream. Sub-streams appear like streams themselves seemingly unassociated stream, raising possibility some progenitor-less Way part single created ancient event.