Searching for Dwarf Galaxies in Gaia DR2 Phase-space Data Using Wavelet Transforms

We present a wavelet-based algorithm to identify dwarf galaxies in the Milky Way ${\it Gaia}$ DR2 data. Our detects overdensities 4D position--proper motion space, making it first search explicitly use velocity information for galaxy candidates. optimize our and quantify its performance by searching mock dwarfs injected into data known satellite galaxies. Comparing results with previous photometric searches, we find that is sensitive undiscovered systems at Galactic latitudes~$\lvert b\rvert>20^{\circ}$ half-light radii larger than 50% detection efficiency threshold Pan-STARRS1 (PS1) (${\it i}$) absolute magnitudes of =$-7<M_V<-3$ distances $32$ kpc $< D < 64$ kpc, ii}$) $M_V< -4$ $64$ 128$ kpc. Based on these results, predict expected discover $5 \pm 2$ new galaxies: four PS1 footprint one outside Dark Energy Survey footprints. apply dataset recover $\sim 830$ high-significance candidates, out which "gold standard" list 200$ candidates based cross-matching potential identified preliminary using EDR3 All candidate lists are publicly distributed future follow-up studies. show improvements astrometric measurements provided increase sensitivity this technique; plan continue refine releases.