Dynamics of the Galactic Bulge using Planetary Nebulae

Abstract

Evidence for a bar at the center of the Milky Way triggered a renewed enthusiasm for dynamical modelling of the Galactic bar-bulge. Our goal is to compare the kinematics of a sample of tracers, planetary nebulae, widely distributed over the bulge with the corresponding kinematics for a range of models of the inner Galaxy. Three of these models are N-body barred systems arising from the instabilities of a stellar disk (Sellwood, Fux and Kalnajs), and one is a Schwarzschild system constructed to represent the 3D distribution of the COBE/DIRBE near-IR light and then evolved as an N-body system for a few dynamical times (Zhao). For the comparison of our data with the models, we use a new technique developed by Saha (1998). The procedure finds the parameters of each model, i.e. the solar galactocentric distance R_o in model units, the orientation angle phi, the velocity scale (in km/s per model unit), and the solar tangential velocity which best fit the data.

48 pages (Latex), 30 figures (PS), accepted for pub. in AJ

References in corpus (5)

• Dynamics of Barred Galaxies
• The Nature of Boxy/Peanut-Shaped Bulges in Spiral Galaxies
• The properties of the Galactic bar implied by gas kinematics in the inner Milky Way
• New constraints on a triaxial model of the Galaxy
• A Dynamical Model of the Inner Galaxy

Cited by in corpus (30)

• The Galaxy in Context: Structural, Kinematic and Integrated Properties
• Our Milky Way as a Pure-Disk Galaxy -- A Challenge for Galaxy Formation
• The VST Photometric Halpha Survey of the Southern Galactic Plane and Bulge (VPHAS+)
• The Bulge Radial Velocity Assay (BRAVA): II. Complete Sample and Data Release
• Chemodynamical history of the Galactic Bulge
• Made-to-Measure models of the Galactic Box/Peanut bulge: stellar and total mass in the bulge region
• Stellar Proper Motions in the Galactic Bulge from deep HST ACS/WFC Photometry
• The Bulge Radial Velocity Assay (BRAVA): I. Techniques and a Rotation Curve
• The Bulge Radial Velocity Assay (BRAVA): I. Sample Selection and a Rotation Curve
• Models for the Gravitational Field of the Galactic Bar. An Application to Stellar Orbits in the Galactic Plane and Orbits of Some Globular Clusters
• The Pattern Speed of the OH/IR Stars in the Milky Way
• The Vertical X-shaped Structure in the Milky Way: Evidence from a Simple Boxy Bulge Model
• Planetary nebulae in the direction of the Galactic bulge: On nebulae with emission-line central stars
• Metallicity and kinematics of the bar in-situ
• Proper Motions in the Galactic Bulge: Plaut's Window
• Correlations between kinematics and metallicity in the Galactic bulge: a review
• New Planetary Nebulae in the Galactic Bulge region with l>0deg - I. Discovery method and first results
• Chemical Study of the Metal-rich Globular Cluster NGC 5927
• The vertical Na-O relation in the bulge globular cluster NGC 6553
• New Planetary Nebulae in the Galactic Bulge region with l>0deg - II
• SiO Masers in the Galactic Bulge and Disk: Kinematics from the BAaDE Survey
• Orbits of globular clusters computed with dynamical friction in the Galactic anisotropic velocity dispersion field
• The Galactic Bulge: A Review
• New groups of planetary nebulae with peculiar dust chemistry towards the Galactic bulge
• Bayesian isochrone fitting and stellar ages
• The populations of planetary nebulae in the direction of the Galactic bulge
• A new look at the kinematics of the bulge from an N-body model
• Kinematics and Composition of the Galactic Bulge: Recent Progress
• The outer halos of elliptical galaxies
• Hunting for Planetary Nebulae toward the Galactic Center