Despite many searches, the particle nature of dark matter remains elusive.  Astrophysical probes, such as stellar streams, are playing an increasing role in constraining the parameter space of dark matter models.  Depending on the behavior of dark matter, we might expect a different number of streams, streams made up of different stellar populations, or altered stream structure.  I will present the first detailed study of dissipative dark matter effects on stellar streams.  Using the FIRE galaxy formation model, I will compare a Milky Way-mass galaxy with atomic dark matter (ADM) and cold dark matter (CDM).  The dissipative nature of atomic dark matter allows for the formation of dense compact objects that enhance the central density of satellite galaxies, making them more resistant to tidal disruption.  Stellar streams in the ADM simulation form later and continue star formation for a longer in their evolution, which alters the stellar chemical abundances.  Furthermore, a population of low-mass satellites with high ADM mass fractions survive at low pericenter distances, which may affect the observable population of low mass streams.  The results of this study should generalize to other dark matter models that lead to inner-density enhancements, such as self-interacting or decaying dark matter, and show that stellar streams are a valuable tool for establishing the nature of dark matter.

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