The Millennium Arecibo 21-CM Absorption Line Survey. II. Properties of the Warm and Cold Neutral Media

Abstract

We use the Gaussian-fit results of Paper I to investigate the properties of interstellar HI in the Solar neighborhood. The Warm and Cold Neutral Media (WNM and CNM) are physically distinct components. The CNM spin temperature histogram peaks at about 40 K. About 60% of all HI is WNM. At z=0, we derive a volume filling fraction of about 0.50 for the WNM; this value is very rough. The upper-limit WNM temperatures determined from line width range upward from about 500 K; a minimum of about 48% of the WNM lies in the thermally unstable region 500 to 5000 K. The WNM is a prominent constituent of the interstellar medium and its properties depend on many factors, requiring global models that include all relevant energy sources, of which there are many. We use Principal Components Analysis, together with a form of least squares fitting that accounts for errors in both the independent and dependent parameters, to discuss the relationships among the four CNM Gaussian parameters. The spin temperature T_s and column density N(HI) are, approximately, the two most important eigenvectors; as such, they are sufficient, convenient, and physically meaningful primary parameters for describing CNM clouds. The Mach number of internal macroscopic motions for CNM clouds is typically 2.5, but there are wide variations. We discuss the historical tau-T_s relationship in some detail and show that it has little physical meaning. We discuss CNM morphology using the CNM pressure known from UV stellar absorption lines. Knowing the pressure allows us to show that CNM structures cannot be isotropic but instead are sheetlike, with length-to-thickness aspect ratios ranging up to about 280. We present large-scale maps of two regions where CNM lies in very large ``blobby sheets''.

Revised submission to Ap.J. Changes include: (1) correction of turbulent Mach number in equation 16 and figure 12; the new typical value is 1.3 versus the old, incorrect value 2.5. (2) smaller typeface for the astro-ph version to conserve paper. 60 pages, 16 figures

References in corpus (11)

• The Milky Way in Molecular Clouds: A New Complete CO Survey
• The Distribution of Thermal Pressures in the Interstellar Medium from a Survey of C I Fine-Structure Excitation
• The Millennium Arecibo 21-cm Absorption Line Survey. I. Techniques and Gaussian Fits
• The Giant Flare of 1998 August 27 from SGR 1900+14: I. An Interpretive Study of BeppoSAX and Ulysses Observations
• The Spin Temperature of Warm Interstellar H I
• The Temperature Distribution in Turbulent Interstellar Gas
• New Temperatures of Diffuse Interstellar Gas: Thermally Unstable Gas
• The Global Structure and Evolution of a Self-Gravitating Multi-phase Interstellar Medium in a Galactic Disk
• Faint, Large-scale H-Alpha Filaments in the Milky Way
• An Extinction Study of the Taurus Dark Cloud Complex
• Models of Veritcal Disturbances in the Interstellar Medium

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• Properties of atomic hydrogen gas in the Galactic plane from THOR 21-cm absorption spectra: a comparison with the high latitude gas
• The pros and cons of the inversion method approach to derive 3D dust emission properties of the ISM: the Hi-GAL field centred on (l,b)=(30${}^{\circ }$,0${}^{\circ }$)
• Shocks in the warm neutral medium I -- Theoretical model
• Tiny-scale Structure Discovered toward PSR B1557$-$50
• The cold neutral medium in filaments at high Galactic latitudes
• The FAST HI 21-cm absorption blind survey. II. -- Statistic Exploration for Associated and Intervening systems
• Precise Measurements of CH Maser Emission and Its Abundance in Translucent Clouds
• Tracing the Formation of Molecular Clouds in a Low-Metallicity Galaxy: A HI Narrow Self-Absorption Survey of the Large Magellanic Cloud
• The MeerKAT Absorption Line Survey (MALS) data release 3: Cold atomic gas associated with the Milky Way
• A Global Census of Metals in the Universe
• Optical Reddening, Integrated HI Optical Depth, Total Hydrogen Column Density
• Narrow-line HI and cold structures in the ISM
• Shocks and Molecules in Diffuse Interstellar Cloud Pairs
• Effects of Forcing on Shocks and Energy Dissipation in Interstellar and Intracluster Turbulences
• The nearby interstellar medium towards alpha Leo -- UV observations and modeling of a warm cloud within hot gas
• A neutral hydrogen absorption study of cold gas in the outskirts of the Magellanic Clouds using the GASKAP-HI survey
• Diagnostics of magnetohydrodynamic modes in the ISM through synchrotron polarization statistics
• The Density-Magnetic Field Relation in the Atomic ISM
• Considerations with stacking absorption spectra: cold HI gas in cirrus region of the Milky Way
• FAST search for circumstellar atomic hydrogen. II. Is BD+303639 an interacting planetary nebula?
• CO and HI observations of an enigmatic cloud
• Wind of Change: Faraday Rotation in a Simulated Large Magellanic Cloud
• The CO-H2 conversion factor of diffuse ISM: Bright 12CO emission also traces diffuse gas
• Tiny-Scale Properties within the Interstellar Medium towards PSR J1644$-$4559: I. Observational Evidence of Turbulence-induced Tiny Scale Atomic Structures
• Cold atomic gas identified by HI self-absorption. Cold atomic clouds toward giant molecular filaments
• HI 21-cm Absorption Associated with Foreground Galaxies on Top of Quasars
• 3D HD and MHD Adaptive Mesh Refinement Simulations of the Global and Local ISM
• First detections of CO absorption in the Magellanic Clouds and direct measurement of the CO-to-H${}_2$ ratio
• On the scale-height of the molecular gas disc in Milky Way-like galaxies
• Are Stellar Embryos in Perseus Radio-Synchrotron Emitters? Statistical data analysis with Herschel and LOFAR paving the way for the SKA
• Acceleration and clustering of cosmic dust in a gravoturbulent gas -- I. Numerical simulation of the nearly Jeans-unstable case
• Research on the Interstellar Medium and Star Formation in the Galaxy: An Indian Perspective
• The contribution of neutral gas to Faraday tomographic data at low frequencies. A first extensive comparison between real and synthetic data
• Dynamical Evolution of a Supernova Driven Turbulent Interstellar Medium
• The MACH HI absorption survey I: Physical conditions of cold atomic gas outside of the Galactic plane
• The cosmic-ray puzzle and the census of the interstellar medium: the Fermi LAT view of Cassiopeia, Cepheus and the Perseus arm
• Interstellar medium and star formation studies with the Square Kilometre Array
• Hydrogen in diffuse molecular clouds in the Milky Way: Atomic column densities and molecular fraction along prominent lines of sight
• The Interstellar Medium and Star Formation in Dwarf Galaxies
• The Neutral Atomic Hydrogen in the solar neighborhood (NeAtHood) project I. Ghost in the shell: Neutral atomic hydrogen in the extended Orion nebula