Evidence of a vertical kinematic oscillation beyond the Radcliffe Wave
arXiv:2112.08390 · doi:10.1051/0004-6361/202142899
Abstract
The Radcliffe Wave (RW) is a recently discovered sinusoidal vertical feature of dense gas in the proximity of the Sun. In the disk plane, it is aligned with the Local Arm. However, the origin of its vertical undulation is still unknown. This study constrains the kinematics of the RW, using young stars and open clusters as tracers, and explores the possibility of this oscillation being part of a more extended vertical mode. We study the median vertical velocity trends of the young stars and clusters along with the RW and extend it further to the region beyond it. We discover a kinematic wave in the Galaxy, distinct from the warp, with the amplitude of oscillation depending on the age of the stellar population. We perform a similar analysis in the N-body simulation of a satellite as massive as the Sagittarius dwarf galaxy impacting the galactic disk. When projected in the plane, the spiral density wave induced by the satellite impact is aligned with the RW, suggesting that both may be the response of the disk to an external perturbation. However, the observed kinematic wave is misaligned. It appears as a kinematic wave travelling radially, winding up faster than the density wave matched by the RW, questioning its origin. If a satellite galaxy is responsible for this kinematic wave, we predict the existence of a vertical velocity dipole that should form across the disk and this may be measurable with the upcoming Gaia DR3 and DR4.
Accepted for publication in Astronomy & Astrophysics Letters
References in corpus (13)
- Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
- Trigonometric Parallaxes Of High-Mass Star Forming Regions: Our View Of The Milky Way
- Painting a portrait of the Galactic disc with its stellar clusters
- A Compendium of Distances to Molecular Clouds in the Star Formation Handbook
- A Galactic-scale gas wave in the Solar Neighborhood
- Is the Milky Way ringing? The hunt for high velocity streams
- A Magellanic Origin for the Warp of the Galaxy
- Hic sunt dracones: Cartography of the Milky Way spiral arms and bar resonances with Gaia Data Release 2
- Local spiral structure based on the Gaia EDR3 parallaxes
- The Formation of a Stellar Association in the NGC 7000/IC 5070 Complex: Results from Kinematic Analysis of Stars and Gas
- Corrugations in the Disk of the Edge-On Spiral Galaxy IC2233
- Wobbly discs -- corrugations seen in the dust lanes of edge-on galaxies
- The substructure of the Perseus star forming region: A survey with Gaia DR2