Jeans modelling of the Milky Way's nuclear stellar disc

Abstract

The nuclear stellar disc (NSD) is a flattened stellar structure that dominates the gravitational potential of the Milky Way at Galactocentric radii $30\lesssim R\lesssim 300\mathrm{pc}$. In this paper, we construct axisymmetric Jeans dynamical models of the NSD based on previous photometric studies and we fit them to line-of-sight kinematic data of APOGEE and SiO maser stars. We find that (i) the NSD mass is lower but consistent with the mass independently determined from photometry by Launhardt et al. (2002). Our fiducial model has a mass contained within spherical radius $r=100\mathrm{pc}$ of $M(r<100\mathrm{pc})=3.9\pm 1\times 10^8{\mathrm{M}}_{\odot }$ and a total mass of $M_{\mathrm{NSD}}=6.9\pm 2\times 10^8{\mathrm{M}}_{\odot }$. (ii) The NSD might be the first example of a vertically biased disc, i.e. with ratio between the vertical and radial velocity dispersion ${\sigma }_z/{\sigma }_R>1$. Observations and theoretical models of the star-forming molecular gas in the central molecular zone suggest that large vertical oscillations may be already imprinted at stellar birth. However, the finding ${\sigma }_z/{\sigma }_R>1$ depends on a drop in the velocity dispersion in the innermost few tens of parsecs, on our assumption that the NSD is axisymmetric, and that the available (extinction corrected) stellar samples broadly trace the underlying light and mass distributions, all of which need to be established by future observations and/or modelling. (iii) We provide the most accurate rotation curve to date for the innermost $500\mathrm{pc}$ of our Galaxy.

arXiv commentAccepted for publication in MNRAS

References in corpus (65)

• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• The Apache Point Observatory Galactic Evolution Experiment (APOGEE)
• The Galaxy in Context: Structural, Kinematic and Integrated Properties
• The Sixteenth Data Release of the Sloan Digital Sky Surveys: First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra
• Adaptive spatial binning of integral-field spectroscopic data using Voronoi tessellations
• A geometric distance measurement to the Galactic Center black hole with 0.3% uncertainty
• The Geneva-Copenhagen Survey of the Solar neighbourhood III. Improved distances, ages, and kinematics
• Measuring the inclination and mass-to-light ratio of axisymmetric galaxies via anisotropic Jeans models of stellar kinematics
• The Nuclear Bulge of the Galaxy. III. Large-Scale Physical Characteristics of Stars and Interstellar Matter
• Target Selection for the Apache Point Observatory Galactic Evolution Experiment (APOGEE)
• Secular Evolution in Disk Galaxies
• A 100-parsec elliptical and twisted ring of cold and dense molecular clouds revealed by Herschel around the Galactic Center
• Reconstructing the stellar mass distributions of galaxies using S4G IRAC 3.6 and 4.5 micron images: II. The conversion from light to mass
• On Galactic density modeling in the presence of dust extinction
• The dynamical evolution of molecular clouds near the Galactic Centre - I. Orbital structure and evolutionary timeline
• Gas Dynamics and Large-Scale Morphology of the Milky Way Galaxy
• The APOGEE red-clump catalog: Precise distances, velocities, and high-resolution elemental abundances over a large area of the Milky Way's disk
• Molecular gas kinematics within the central 250 pc of the Milky Way
• Dynamical heating across the Milky Way disc using APOGEE and $Gaia$
• Surface Brightness Profile of the Milky Way's Nuclear Star Cluster
• The old nuclear star cluster in the Milky Way: dynamics, mass, statistical parallax, and black hole mass
• Gas flow models in the Milky Way embedded bars
• Interstellar Extinction Law toward the Galactic Center II: V, J, H, and Ks Bands
• Large scale kinematics and dynamical modelling of the Milky Way nuclear star cluster
• Time Inference with MUSE in Extragalactic Rings (TIMER): Properties of the Survey and High-Level Data Products
• Gas flow in barred potentials
• Age velocity dispersion relations and heating histories in disc galaxies
• Early formation and recent starburst activity in the nuclear disc of the Milky Way
• Gas flow in barred potentials - III. Effects of varying the Quadrupole
• Estimation of the Tilt of the Stellar Velocity Ellipsoid from RAVE and Implications for Mass Models
• The formation of stellar nuclear discs in bar-induced gas inflows
• A radial age gradient in the geometrically thick disk of the Milky Way
• Simulations of the Milky Way's central molecular zone -- II. Star formation
• Efficient solution of the anisotropic spherically-aligned axisymmetric Jeans equations of stellar hydrodynamics for galactic dynamics
• GALACTICNUCLEUS: A high angular resolution $JH{K}_s$ imaging survey of the Galactic Centre. I. Methodology, performance, and near-infrared extinction towards the Galactic Centre
• Galactic kinematics and dynamics from RAVE stars
• The H2O southern Galactic Plane Survey(HOPS): NH3 (1,1) and (2,2) catalogues
• A theoretical explanation for the Central Molecular Zone asymmetry
• Another bar in the Bulge
• GALACTICNUCLEUS: A high-angular-resolution JHKs imaging survey of the Galactic centre II. First data release of the catalogue and the most detailed CMDs of the GC
• The inner Galactic bulge: evidence for a nuclear bar?
• New constraints on the structure of the nuclear stellar cluster of the Milky Way from star counts and MIR imaging
• 86 GHz SiO maser survey of late-type stars in the Inner Galaxy III. Interstellar extinction and colours of the SiO targets
• Magnetically Confined Interstellar Hot Plasma in the Nuclear Bulge of our Galaxy
• Nuclear Stellar Disks in Spiral Galaxies
• The geometry of the gas surrounding the Central Molecular Zone: on the origin of localised molecular clouds with extreme velocity dispersions
• 86 GHz SiO maser survey of late-type stars in the Inner Galaxy. I. Observational data
• Age Dating the Galactic Bar with the Nuclear Stellar Disc
• Kinematic Detection of the Galactic Nuclear Disc
• Kinematic deprojection and mass inversion of spherical systems of known velocity anisotropy
• Disk heating agents across the Hubble sequence
• Origin of the high v_los feature in the Galactic bar
• First Gaia dynamical model of the Milky Way disc with six phase space coordinates: a test for galaxy dynamics
• Star formation history and metallicity in the Galactic inner bulge revealed by the red giant branch bump
• The distribution of maser stars in the inner Milky Way: the effect of a weak, rotating bar
• Kinematics of classical Cepheids in the Nuclear Stellar Disk
• Variability of the near-infrared extinction curve towards the Galactic centre
• 86 GHz SiO maser survey of late-type stars in the Inner Galaxy II. Infrared photometry of the SiO Target Stars
• Testing the Prediction of Fuzzy Dark Matter Theory in the Milky Way Center
• Resonant Orbits and the High Velocity Peaks Towards the Bulge
• The Tilt of the Local Velocity Ellipsoid as Seen by Gaia
• Revisiting the Stellar Velocity Ellipsoid - Hubble type relation: observations versus simulations
• Disk heating and bending instability in galaxies with counterrotation
• Three-dimensional Keplerian orbit-superposition models of the nucleus of M31
• Disk mass and disk heating in the spiral galaxy NGC 3223

Cited by in corpus (30)

• Gas Dynamics in the Galaxy: Total Mass Distribution and the Bar Pattern Speed
• The Milky Way's nuclear stellar disc: A dynamically cool and metal-rich component formed from the Central Molecular Zone?
• Testing kinematic distances under a realistic Galactic potential
• GALACTICNUCLEUS: A high-angular-resolution $JH{K}_s$ imaging survey of the Galactic centre. IV. Extinction maps and de-reddened photometry
• Radial halo substructure in harmony with the Galactic bar
• The nuclear star cluster and nuclear stellar disc of the Milky Way: Different stellar population and star formation history
• A KMOS survey of the nuclear disk of the Milky Way I: Survey design and metallicities
• Composite Bulges -- II. Classical Bulges and Nuclear Discs in Barred Galaxies: The Contrasting Cases of NGC 4608 and NGC 4643
• Distance to three molecular clouds in the central molecular zone
• Study of the excess Fe XXV line emission in the central degrees of the Galactic centre using XMM-Newton data
• Stellar Populations in the Transition Region of Nuclear Star Cluster and Nuclear Stellar Disc
• Evidence of an age gradient along the line of sight in the nuclear stellar disc of the Milky Way
• Kinematic data rebuild the Nuclear star cluster as the most metal rich region of the Galaxy
• Measuring the Orbits of the Arches and Quintuplet Clusters using HST and Gaia: Exploring Scenarios for Star Formation Near the Galactic Center
• A first glimpse at the line-of-sight structure of the Milky Way's nuclear stellar disc
• Disc galaxies are still settling: The discovery of the smallest nuclear discs and their young stellar bars
• Distance to the Brick cloud using stellar kinematics
• Evidence of Deep Mixing in IRS 7, a Cool Massive Supergiant Member of the Galactic Nuclear Star Cluster
• Smooth kinematic and metallicity gradients reveal that the Milky Way's nuclear star cluster and disc might be part of the same structure
• A spectroscopic map of the Galactic centre -- Observations and resolved stars
• Nonthermal filaments from the tidal destruction of clouds in the Galactic center
• Dynamical mass distribution and velocity structure of the Galactic centre
• Dynamical streams in the local stellar halo
• The JWST-NIRCam View of Sagittarius C. II. Evidence for Magnetically Dominated HII Regions in the CMZ
• Jeans modeling of axisymmetric galaxies with multiple stellar populations
• The Galactic Center with Roman
• 3D CMZ V: A new orbital model of our Galaxy's Center, informed by data across the electromagnetic spectrum
• Self-consistent modelling of the Milky Way's Nuclear Stellar Disc
• Clustered Star Formation in the center of NGC 253 Contributes to Driving the Ionized Nuclear Wind
• X-ray emission of the Nuclear Stellar Disk as seen by SRG/ART-XC