Detection of Extraplanar Diffuse Ionized Gas in M83

Abstract

We present the first kinematic study of extraplanar diffuse ionized gas (eDIG) in the nearby, face-on disk galaxy M83 using optical emission-line spectroscopy from the Robert Stobie Spectrograph on the Southern African Large Telescope. We use a Markov Chain Monte Carlo method to decompose the [NII]$\lambda \lambda$6548, 6583, H$\alpha$, and [SII]$\lambda \lambda$6717, 6731 emission lines into HII region and diffuse ionized gas emission. Extraplanar, diffuse gas is distinguished by its emission-line ratios ([NII]$\lambda$6583/H$\alpha \gtrsim 1.0$) and its rotational velocity lag with respect to the disk ($\Delta v=-24$ km/s in projection). With interesting implications for isotropy, the velocity dispersion of the diffuse gas, $\sigma =96$ km/s, is a factor of a few higher in M83 than in the Milky Way and nearby, edge-on disk galaxies. The turbulent pressure gradient is sufficient to support the eDIG layer in dynamical equilibrium at an electron scale height of $h_z=1$ kpc. However, this dynamical equilibrium model must be finely tuned to reproduce the rotational velocity lag. There is evidence of local bulk flows near star-forming regions in the disk, suggesting that the dynamical state of the gas may be intermediate between a dynamical equilibrium and a galactic fountain flow. As one of the first efforts to study eDIG kinematics in a face-on galaxy, this study demonstrates the feasibility of characterizing the radial distribution, bulk velocities, and vertical velocity dispersions in low-inclination systems.

arXiv comment19 pages, 11 figures, accepted for publication in the Astrophysical Journal

References in corpus (30)

• Cosmic-Ray Rejection by Laplacian Edge Detection
• The Wisconsin H-Alpha Mapper Northern Sky Survey
• The cold gaseous halo of NGC 891
• Extending the Nearby Galaxy Heritage with WISE: First Results from the WISE Enhanced Resolution Galaxy Atlas
• Deep H I Survey of the Spiral Galaxy NGC 2403
• WHAM Observations of H-Alpha, [S II], and [N II] toward the Orion and Perseus Arms: Probing the Physical Conditions of the Warm Ionized Medium
• The Hubble flow around the CenA / M83 galaxy complex
• A Dynamical Model for the Extra-planar Gas in Spiral Galaxies
• Modeling the Warm Ionized Interstellar Medium and Its Impact on Elemental Abundance Studies
• A Multiwavelength Optical Emission Line Survey of Warm Ionized Gas in the Galaxy
• A VLT study of metal-rich extragalactic H II regions. I. Observations and empirical abundances
• An H-alpha survey aiming at the detection of extraplanar diffuse ionized gas in halos of edge-on spiral galaxies. I. How common are gaseous halos among non-starburst galaxies?
• Further Spectroscopy of the Diffuse Ionized Gas in NGC 891 and Evidence for a Secondary Source of Ionization
• Ionization Sources and Physical Conditions in the Diffuse Ionized Gas Halos of Four Edge-On Galaxies
• The Ionized Gas in Local Starburst Galaxies: Global and Small--Scale Feedback from Star Formation
• Kinematics of Diffuse Ionized Gas Halos: A Ballistic Model of Halo Rotation
• Integral Field Unit Observations of NGC 891: Kinematics of the Diffuse Ionized Gas Halo
• Integral Field Unit Observations of NGC 4302: Kinematics of the Diffuse Ionized Gas Halo
• Properties of discrete X-ray sources in the starburst spiral galaxy M83
• Planetary Nebulae in Face-On Spiral Galaxies. III. Planetary Nebula Kinematics and Disk Mass
• Kinematics of the Ionised Gas in the Spiral Galaxy NGC 2403
• Imaging Fabry-Perot Spectroscopy of NGC 5775: Kinematics of the Diffuse Ionized Gas Halo
• A Deep Chandra ACIS Survey of M83
• X-ray sources in the starburst spiral galaxy M83: nuclear region and discrete source population
• Emission Line Ratios and Variations in Temperature and Ionization State in the Diffuse Ionized Gas of Five Edge-on Galaxies
• SDSS IV MaNGA - Rotation Velocity Lags in the Extraplanar Ionized Gas from MaNGA Observations of Edge-on Galaxies
• Neutral hydrogen and magnetic fields in M83 observed with the SKA Pathfinder KAT-7
• High-Velocity Clouds in the Nearby Spiral Galaxy M 83
• Testing a Dynamical Equilibrium Model of the Extraplanar Diffuse Ionized Gas in NGC 891
• Large-scale shock-ionized and photo-ionized gas in M83: the impact of star formation

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• The EDGE-CALIFA Survey: Molecular and Ionized Gas Kinematics in Nearby Galaxies
• The Effects of Diffuse Ionized Gas and Spatial Resolution on Metallicity Gradients: TYPHOON Two-Dimensional Spectrophotometry of M83
• The MUSE Atlas of Disks (MAD): Ionized gas kinematic maps and an application to Diffuse Ionized Gas
• Galactic Gas Flows from Halo to Disk: Tomography and Kinematics at the Milky Way's Disk-Halo Interface
• Stellar feedback in M83 as observed with MUSE -- I. Overview, an unprecedented view of the stellar and gas kinematics and evidence of outflowing gas
• A geostatistical analysis of multiscale metallicity variations in galaxies [II]: Predicting the metallicities of Hii and diffuse ionised gas regions via universal kriging
• A Dynamical Study of Extraplanar Diffuse Ionized Gas in NGC 5775
• Deep Chandra observations of diffuse hot plasma in M83
• A Kinematic Analysis of Ionised Extraplanar Gas in the Spiral Galaxies NGC 3982 and NGC 4152
• Spatially Resolved Properties of Extraplanar Diffuse Ionized Gas in NGC3511 and NGC3513