The turbulent gas structure in the centers of NGC253 and the Milky Way

Abstract

We compare molecular gas properties in the starbursting center of NGC253 and the Milky Way Galactic Center (GC) on scales of ~1-100 pc using dendograms and resolution-, area- and noise-matched datasets in CO (1-0) and CO (3-2). We find that the size-line width relations in NGC253 and the GC have similar slope, but NGC253 has larger line widths by factors of ~2-3. The ${\sigma }^2/R$ dependency on column density shows that, in the GC, on scales of 10-100 pc the kinematics of gas over $N>3\times 10^{21}$ cm${}^{-2}$ are compatible with gravitationally bound structures. In NGC253 this is only the case for column densities $N>3\times 10^{22}$ cm${}^{-2}$. The increased line widths in NGC253 originate in the lower column density gas. This high-velocity dispersion, not gravitationally self-bound gas is likely in transient structures created by the combination of high average densities and feedback in the starburst. The high densities turns the gas molecular throughout the volume of the starburst, and the injection of energy and momentum by feedback significantly increases the velocity dispersion at a given spatial scale over what is observed in the GC.

arXiv comment13 pages, 3 figures, 4 tables; accepted for publication in the Astrophysical Journal

References in corpus (60)

• Astropy: A Community Python Package for Astronomy
• The NumPy array: a structure for efficient numerical computation
• Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies
• Binary companions of evolved stars in APOGEE DR14: Search method and catalog of ~5,000 companions
• The CO-to-H2 Conversion Factor
• The Milky Way in Molecular Clouds: A New Complete CO Survey
• Secular Evolution and the Formation of Pseudobulges in Disk Galaxies
• A geometric distance measurement to the Galactic Center black hole with 0.3% uncertainty
• Re-examining Larson's Scaling Relationships in Galactic Molecular Clouds
• The Boston University-Five College Radio Astronomy Observatory Galactic Ring Survey
• Absorption-Line Probes of Gas and Dust in Galactic Superwinds
• Structural Analysis of Molecular Clouds: Dendrograms
• Massive molecular outflows and negative feedback in ULIRGs observed by Herschel-PACS
• Variations in the Galactic star formation rate and density thresholds for star formation
• The Equilibrium State of Molecular Regions in the Outer Galaxy
• The Starburst-Driven Molecular Wind in NGC 253 and the Suppression of Star Formation
• The PdBI Arcsecond Whirlpool Survey (PAWS): Environmental Dependence of Giant Molecular Cloud Properties in M51
• 3D Integral Field Observations of Ten Galactic Winds - I. Extended phase (>10 Myr) of mass/energy injection before the wind blows
• Cloud-Scale Molecular Gas Properties in 15 Nearby Galaxies
• Dense gas in the Galactic central molecular zone is warm and heated by turbulence
• Chandra observations of NGC 253. II: On the origin of diffuse X-ray emission in the halos of starburst galaxies
• Spatial distribution of interstellar gas in the innermost 3 kpc of our Galaxy
• ALMA Reveals the Molecular Medium Fueling the Nearest Nuclear Starburst
• Morphology of the Interstellar Cooling Lines Detected by COBE
• Star formation rates and efficiencies in the Galactic Centre
• Physical vs. Observational Properties of Clouds in Turbulent Molecular Cloud Models
• Rotation Curve and Mass Distribution in the Galactic Center --- From Black Hole to Entire Galaxy ---
• A Dynamical Model for the Formation of Gas Rings and Episodic Starbursts Near Galactic Centres
• The linewidth-size relationship in the dense ISM of the Central Molecular Zone
• CO (J=7->6) Observations of NGC 253: Cosmic Ray Heated Warm Molecular Gas
• ALMA Multi-line Imaging of the Nearby Starburst Galaxy NGC 253
• CHIMPS: the ${}^{13}$CO/C${}^{18}$O (J=3-2) Heterodyne Inner Milky Way Plane Survey
• Dense Molecular Gas Tracers in the Outflow of the Starburst Galaxy NGC 253
• A Dynamical Model for Gas Flows, Star Formation, and Nuclear Winds in Galactic Centres
• The VLBA Galactic Plane Survey -- VGaPS
• Structure and star formation in disk galaxies III. Nuclear and circumnuclear H alpha emission
• Forming Super Star Clusters in the Central Starburst of NGC 253
• Spatially resolved optical IFU spectroscopy of the inner superwind of NGC 253
• The Survey of Water and Ammonia in the Galactic Center (SWAG): Molecular Cloud Evolution in the Central Molecular Zone
• Mass inflow rate into the Central Molecular Zone: observational determination and evidence of episodic accretion
• Molecular Superbubbles in the Starburst Galaxy NGC 253
• Star-forming Cloud Complexes in the Central Molecular Zone of NGC 253
• Does External Pressure Explain Recent Results for Molecular Clouds?
• The Effect of Projection on Derived Mass-Size and Linewidth-Size Relationships
• The integrated properties of the molecular clouds from the JCMT CO(3-2) High Resolution Survey
• The ALMA view of GMCs in NGC 300: Physical Properties and Scaling Relations at 10 pc Resolution
• The Stellar Kinematic Center and the True Galactic Nucleus of NGC253
• Linking bar- and interaction-driven molecular gas concentration with centrally-enhanced star formation in EDGE-CALIFA galaxies
• The molecular outflow in NGC253 at a resolution of two parsecs
• Galactic Rings Revisited. I. CVRHS Classifications of 3962 Ringed Galaxies from the Galaxy Zoo 2 Database
• The Structure, Kinematics and Physical Properties of the Molecular Gas in the Starburst Nucleus of NGC 253
• Fire in the Heart: A Characterization of the High Kinetic Temperatures and Heating Sources in the Nucleus of NGC253
• Observation of Acceleration of HI Clouds Within the Fermi Bubbles
• Molecular gas in NUclei of GAlaxies (NUGA) XV. Molecular gas kinematics in the inner 3kpc of NGC6951
• Diverse nuclear star-forming activities in the heart of NGC 253 resolved with ten-pc scale ALMA images
• Assessing the Performance of Molecular Gas Clump Identification Algorithms
• Possible connection between the asymmetry of North Polar Spur and Loop I with Fermi Bubbles
• A thorough view of the nuclear region of NGC 253 - Combined Herschel, SOFIA and APEX dataset
• The Molecular ISM in the Super Star Clusters of the Starburst NGC 253
• Inner rings in disc galaxies: dead or alive

Cited by in corpus (12)

• Which feedback mechanisms dominate in the high-pressure environment of the Central Molecular Zone?
• The Morpho-Kinematic Architecture of Super Star Clusters in the Center of NGC253
• NOEMA High Fidelity Imaging of the Molecular Gas in and around M82
• Fragmentation and kinematics in high-mass star formation: CORE-extension targeting two very young high-mass star-forming regions
• The molecular gas resolved by ALMA in the low-metallicity dwarf merging galaxy Haro 11
• WISDOM Project XII. Clump properties and turbulence regulated by clump-clump collisions in the dwarf galaxy NGC404
• Physics of Non-Universal Larson's Relation
• An ALCHEMI inspection of sulphur-bearing species towards the central molecular zone of NGC 253
• The magnetic field in the Flame nebula
• The Hierarchical Dynamical State of Molecular Gas from 3 to 300 pc in NGC 253
• Impact of the shape of the prestellar density fluctuations on the core mass function
• Kinematics and Feedback in H II regions in the Dwarf Starburst Galaxy IC 10