Dynamics of Stellar Disk Tilting from Satellite Mergers

Understand

The Milky Way's stellar disk can tilt in response to torques that result from infalling satellite galaxies and their associated tidal debris.

• In this work, we explore the dynamics of disk tilting by running N-body simulations of mergers in an isolated, isotropic Milky Way-like host galaxy, varying over satellite virial mass, initial position, and orbit.
• We develop and validate a first-principles understanding of the dynamics that govern how the host galaxy's stellar disk responds to the satellite's dark matter debris.
• We find that the degree of disk tilting can be large for cosmologically-motivated merger histories.