Revisiting the Milky Way dwarf spheroidal galaxies with Gaia DR3
Phys. Rev. D 111, 123026 – Published 20 June, 2025
DOI: https://doi.org/10.1103/nft9-rt7f
Abstract
We present a new survey for the satellites of the Milky Way, including nine known dwarf spheroidals galaxies (dSphs), supplemented with one ultrafaint dwarf Bootes I, based on Gaia DR3 data. Understanding their physical parameters enable the study of evolutionary processes of dwarf galaxies, significant differences between dark matter dominated objects and globular clusters. We identify the more complete and highly reliable star members of our target systems using a novel clustering algorithm; Forest Fire Clustering. We determine the physical parameters of these ten dSphs, including age, metallicity, distance modulus, reddening, structure parameters, and kinematics properties, by fitting observed data to theoretical models. For most systems, the cluster parameters are generally consistent with those presented in published literature. Similarly, our analysis reveal distinctly different half-light radii, with the ten objects having radii larger than , while the globular clusters exhibit radii smaller than . This study updates the census of star members for the dSphs in the Milky Way. With the physical parameters obtained from this work, it provides the groundwork for further investigation into dark matter on smaller scales.