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Modeling the Tidal Tails of the Sagittarius Dwarf Galaxy

David R. Law·Steven R. Majewski·Kathryn V. Johnston·Michael F. Skrutskie
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Abstract

N-body simulations are used to model the tidal disruption of the Sagittarius (Sgr) dwarf galaxy with constraints set by the positions and velocities of M giants in the Sgr tidal arms recently revealed by the Two Micron All-Sky Survey (2MASS). The simulated Sgr dwarf is placed on a variety of orbits within a Milky Way potential parameterized by variable circular velocities, halo flattenings and radial profiles. Two hundred separate test particle orbits have been used to explore a wide range of model Milky Way potentials and dwarf galaxy characteristics. The family of models is delimited by the data to a relatively narrow allowed range of parameters, and then input into N-body simulations. We present our best-fitting model, and discuss the orbital period, apoGalacticon distance, current space velocity, mass-to-light ratio, and other characteristics of the Sgr dwarf. In addition, we discuss the implications of this model for the flattening of the Galactic halo.

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David R. Law, Steven R. Majewski, Kathryn V. Johnston, Michael F. Skrutskie. 2003-09-21. Modeling the Tidal Tails of the Sagittarius Dwarf Galaxy. https://arxiv.org/abs/astro-ph/0309567

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