Stellar halo striations from assumptions of axisymmetry

Understand

Motivated by the LMC's impact on the integral of motion space of the stellar halo, we run an $N$-body merger simulation to produce a population of halo-like stars.

• We subsequently move to a test particle simulation, in which the LMC perturbs this debris.
• When an axisymmetric potential is assumed for the final snapshot of the $N$-body merger remnant, a series of vertical striations in $(L_z, E)$ space form as the LMC approaches its pericentre.
• These result from the formation of overdensities in angular momentum owing to a relationship between the precession rate of near radial orbits and the torquing of these orbits by the LMC.