# Hunting for the Dark Matter Wake Induced by the Large Magellanic Cloud

## TL;DR

This study uses high-resolution simulations to detect the gravitational wake caused by the Large Magellanic Cloud in the Milky Way's dark matter and stellar halos, revealing observable kinematic signatures.

## Contribution

First detailed simulation of the LMC's impact on the MW's dark matter and stellar halos, predicting observable wake signatures for future surveys.

## Key findings

- Pronounced Local and Global wakes in dark matter and stellar halos.
- Distinct kinematic patterns, including radial velocity shifts, caused by the LMC's passage.
- Persistent stellar overdensities tracing the LMC's orbit.

## Abstract

Satellite galaxies are predicted to generate gravitational density wakes as they orbit within the dark matter (DM) halos of their hosts, causing their orbits to decay over time. The recent infall of the Milky Way's (MW) most massive satellite galaxy, the Large Magellanic Cloud (LMC), affords us the unique opportunity to study this process in action. In this work, we present high-resolution ($m_{dm} = 4 \times 10^4 M_{\odot}$ ) N-body simulations of the MW-LMC interaction over the past 2 Gyr. We quantify the impact of the LMC's passage on the density and kinematics of the MW's DM halo and the observability of these structures in the MW's stellar halo. The LMC is found to generate pronounced Local and Global wakes in both the DM and stellar halos, leads to both local overdensities and distinct kinematic patterns that should be observable with ongoing and future surveys. Specifically, the Global Wake will result in redshifted radial velocities of stars in the North and blueshifts in the South, at distances larger than 45 kpc. The Local Wake traces the orbital path of the LMC through the halo (50-200 kpc), resulting in a stellar overdensity with a distinct, tangential kinematic pattern that persists to the present day. The detection of the MW's halo response will constrain: the infall mass of the LMC and its orbital trajectory, the mass of the MW, and it may inform us about the nature of the dark matter particle itself.