A Wave-Corrected Assessment of the Local Midplane

Abstract

As the number of known Galactic structures mounts thanks to the Gaia Space Telescope, it is now pertinent to study methods for disentangling structures occupying the same regions of the Milky Way. Indeed, understanding the precise form of each individual structure and the interactions between structures may aid in understanding their origins and chronology. Moreover, accounting for known structures allows one to probe still finer Galactic structure. In order to demonstrate, we have developed an odd low-pass filter (OLPF) which removes smaller, odd-parity structures like the vertical waves, and use the filtered data to examine the location of the Galaxy's mid-plane. We find that the radial wave identified by Xu et al. (2015) continues inward to at least the Sun's location, with an amplitude that decreases towards the inner, denser parts of the disk, consistent with a simple, qualitative simulation. Additionally, we employ the OLPF results to determine the solar offset, $z_{\odot }$, with smaller structures filtered out. We find that $z_{\odot }=34.2\pm 0.3$ pc.

arXiv comment12 pages, 10 sub figures and one animation across 5 figures. Animation may not work in all pdf-viewing softwares. Accepted in ApJ

References in corpus (32)

• Array Programming with NumPy
• A Universal Density Profile from Hierarchical Clustering
• The Gaia mission
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• Gaia Data Release 2: The astrometric solution
• A geometric distance measurement to the Galactic Center black hole with 0.3% uncertainty
• A dynamically young and perturbed Milky Way disk
• The Effect of the Outer Lindblad Resonance of the Galactic Bar on the Local Stellar Velocity Distribution
• Vertical waves in the solar neighbourhood in Gaia DR2
• Galactoseismology: Discovery of Vertical Waves in the Galactic Disk
• The Milky Way has no thick disk
• Rings and Radial Waves in the Disk of the Milky Way
• The Vertical Structure of the Outer Milky Way HI Disk
• Updated Gaia-2MASS 3D maps of Galactic interstellar dust
• A three-dimensional map of the Milky Way using classical Cepheid variable stars
• A Galactic-scale gas wave in the Solar Neighborhood
• An intuitive 3D map of the Galactic warp's precession traced by classical Cepheids
• Galactic seismology: the evolving "phase spiral" after the Sagittarius dwarf impact
• Characteristics of the Galaxy according to Cepheids
• The Stellar Number Density Distribution in the Local Solar Neighborhood is North-South Asymmetric
• The 4:1 Outer Lindblad Resonance of a long slow bar as a potential explanation for the Hercules stream
• Identifying resonances of the Galactic bar in Gaia DR2: I. Clues from action space
• Revised Geometric Estimates of the North Galactic Pole and the Sun's Height Above the Galactic Midplane
• Multiple phase spirals suggest multiple origins in Gaia DR3
• Milky Way Tomography with K and M Dwarf Stars: the Vertical Structure of the Galactic Disk
• Mapping Milky Way disk perturbations in stellar number density and vertical velocity using Gaia DR3
• Age dissection of the vertical breathing motions in Gaia DR2: evidence for spiral driving
• The Milky Way, Coming into Focus: Precision Astrometry Probes its Evolution, and its Dark Matter
• Applying Noether's theorem to matter in the Milky Way: evidence for external perturbations and non-steady-state effects from Gaia Data Release 2
• Probing Axial Symmetry Breaking in the Galaxy with Gaia Data Release 2
• Axial Asymmetry Studies in Gaia Data Release 2 Yield the Pattern Speed of the Galactic Bar
• Reflection symmetries of Isolated Self-consistent Stellar Systems