Related papers: Delayed phase mixing in the self-gravitating Galac…
The vertical phase-space spirals in the Milky Way are clear evidence of disequilibrium. However, they are challenging to study because phase mixing signals evolve under the influence of many different dynamical processes and can be driven…
We analyse an N-body simulation of the interaction of the Milky Way (MW) with a Sagittarius-like dSph (Sgr), looking for signatures which may be attributed to its orbital history in the phase space volume around the Sun in light of $Gaia$…
Gaia data have revealed vertically asymmetric phase-space structures in the Milky Way (MW) disc, such as phase spirals, indicating vertical oscillations. These oscillations exhibit two distinct modes: the bending mode and the breathing…
We study the dynamics of tidally induced spiral arms in our Galaxy in the context of its encounters with Sagittarius. We built toy models of the interaction between a host and a satellite galaxy using orbital integrations after a tidal…
The vertical distribution of stars in the solar neighbourhood is not in equilibrium but contains a wave signature in both density and velocity space originating from a perturbation. With the discovery of the phase-space spiral in Gaia data…
In 2018, the ESA \Gaia\ satellite discovered a remarkable spiral pattern ("phase spiral") in the $z-V_z$ phase plane throughout the solar neighbourhood, where $z$ and $V_z$ are the displacement and velocity of a star perpendicular to the…
The ongoing merger of the Sagittarius (Sgr) dwarf galaxy with the Milky Way is believed to strongly affect the dynamics of the Milky Way's disc. We present a suite of 13 $N$-body simulations, with 500 million to 1 billion particles,…
Using a single N-body simulation ($N=0.14\times 10^9$) we explore the formation, evolution and spatial variation of the phase-space spirals similar to those recently discovered by Antoja et al. in the Milky Way disk, with Gaia DR2. For the…
We explore the interplay between in-plane and vertical dynamics in stellar discs within the framework of the shearing box approximation. Julian and Toomre used the shearing sheet to show that leading density waves are amplified as they…
We aim to study the phase spiral in the Milky Way (MW) with Gaia DR3. We used an edge detection algorithm to find the border of the phase spiral, allowing us to robustly quantify its shape at different positions and for different…
The discovery of the phase space spirals in the Solar neighborhood in Gaia Data Release 2 has prompted various attempts to understand their origin. A source of bending waves, which has been neglected as a cause of the phase spiral, is…
Prior to its infall, the Sagittarius (Sgr) dwarf galaxy was a major satellite with a mass of $M_{\rm sgr}\sim 10^{11}$ M$_\odot$. For the past $5-6~\mathrm{Gyr}$ , it has been heavily stripped by the Milky Way (MW), losing most of its mass…
We use N-body simulations to explore the possibility that the Sagittarius (Sgr) dwarf galaxy was originally a late-type, rotating disc galaxy, rather than a non-rotating, pressure-supported dwarf spheroidal galaxy, as previously thought. We…
We revisit the dynamics of razor-thin, stone-cold, self-gravitating discs. By recasting the equations into standard cylindrical coordinates, the linearised vertical dynamics of an exponential disc can be followed for several gigayears on a…
Understanding the spiral arms of the Milky Way (MW) remains a key open question in galactic dynamics. Tidal perturbations, such as the recent passage of the Sagittarius dwarf galaxy (Sgr), could play a significant role in exciting them. We…
The tidal stirring model envisions the formation of dwarf spheroidal (dSph) galaxies in the Local Group via the tidal interaction of disky dwarf systems with a larger host galaxy like the Milky Way. These progenitor disks are embedded in…
Satellites orbiting disc galaxies can induce phase space features such as spirality, vertical heating and phase-mixing in their discs. Such features have also been observed in our own Galaxy, but the complexity of the Milky Way disc has…
We investigate the spatiotemporal structure of simulations of the homogeneous slab and isothermal plane models for the vertical motion in the Galactic disc. We use Dynamic Mode Decomposition (DMD) to compute eigenfunctions of the simulated…
We use test-particle integrations to show that epicyclic motions excited by a pericentre passage of a dwarf galaxy could account for bulk vertical velocity streaming motions recently observed in the Galactic stellar disc near the Sun. We…
The second data release of ESA's $Gaia$ mission revealed numerous signatures of disequilibrium in the Milky Way's disc. These signatures are seen in the planar kinematics of stars, which manifest as ridges and ripples in $R-v_{\phi}$, and…