Year: 2017
Type: article
Abstract: We study the kinematic properties of the Eastern Banded Structure (EBS) and Hydra I overdensity using exquisite proper motions derived from the Sloan Digital Sky Survey (SDSS) and Gaia source catalogue. Main sequence turn-off stars in the vicinity of the EBS are identified from SDSS photometry; we use the proper motions and, where applicable, spectroscopic measurements of these stars to probe the kinematics of this apparent stream. We find that the EBS and Hydra I share common kinematic and chemical properties with the nearby Monoceros Ring. In particular, the proper motions of the EBS, like Monoceros, are indicative of prograde rotation (Vϕ ∼ 180–220 km s−1), which is similar to the Galactic thick disc. The kinematic structure of stars in the vicinity of the EBS suggests that it is not a distinct stellar stream, but rather marks the ‘edge’ of the Monoceros Ring. The EBS and Hydra I are the latest substructures to be linked with Monoceros, leaving the Galactic anti-centre a mess of interlinked overdensities which likely share a unified, Galactic disc origin.
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Awards: G163854943, G3207356259, G349053094, Testing the cold dark matter paradigm with dwarf galaxies and stellar streams in Gaia and LSST, Astronomy Observation and Theory Consolidated Grant 2016-2019, Measuring the Lumpiness of Dark Matter With Tidal Streams, WEAVE Detectors Completion, G653891685, Durham Astronomy Consolidated Grant 2017-2020, G896728979
OpenAlex ID: W2758892404