pith. machine review for the scientific record. sign in

arxiv: 2605.10711 · v1 · submitted 2026-05-11 · 🌌 astro-ph.GA

Recognition: 2 theorem links

· Lean Theorem

Gas Phase Distribution in the Neutral ISM: A Comparison between Observation and Numerical Simulation

Atanu Koley
Authors on Pith no claims yet

Pith reviewed 2026-05-12 04:19 UTC · model grok-4.3

classification 🌌 astro-ph.GA
keywords neutral interstellar mediumHI 21-cm linecold neutral mediumwarm neutral mediumunstable neutral mediumspin temperaturephase fractionsnumerical simulations
0
0 comments X

The pith

Observations of neutral hydrogen find roughly 20 percent cold, 33 percent unstable, and 48 percent warm gas, matching numerical simulations.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper analyzes 21-centimeter emission and absorption spectra to measure how neutral interstellar gas divides into temperature-based phases. It applies fixed spin-temperature thresholds to separate the gas and computes the resulting mass fractions. These observed fractions align with the output of numerical simulations that incorporate turbulence. The large share of gas in the intermediate phase shows that turbulence prevents a simple two-phase structure. More sensitive absorption data would tighten the measured fractions.

Core claim

Modeling of the observational spectra yields 19.8 percent of the gas in the cold phase below 250 K spin temperature, 32.5 percent in the unstable phase between 250 K and 5000 K, and 47.8 percent in the warm phase above 5000 K. This three-phase breakdown reproduces the distribution found in numerical simulations of the neutral interstellar medium.

What carries the argument

Spin-temperature boundaries that classify neutral gas into cold, unstable, and warm phases, allowing quantitative comparison of observed mass fractions with simulation results.

If this is right

  • Turbulence sustains a sizable fraction of gas in the thermally unstable regime between the cold and warm media.
  • The neutral interstellar medium maintains approximate pressure equilibrium across the three phases.
  • The observed fractions confirm that simulations with turbulence reproduce the thermal structure of the neutral gas.
  • Deeper absorption measurements will reduce uncertainty in the exact phase fractions.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • If the same fractions appear in other galaxies, the distribution could serve as a standard template for interstellar-medium models.
  • Changes in the unstable fraction across different galactic regions would directly trace local turbulence intensity.
  • Adopting these fractions in galaxy-evolution calculations could refine predictions for cooling rates and star-formation efficiency.

Load-bearing premise

The chosen spin-temperature cutoffs of 250 K and 5000 K correctly mark the boundaries between the three phases without substantial misclassification.

What would settle it

A high-sensitivity absorption survey that measures an unstable-phase fraction below 25 percent or above 40 percent would show that the temperature thresholds or the simulation comparison is inaccurate.

Figures

Figures reproduced from arXiv: 2605.10711 by Atanu Koley.

Figure 1
Figure 1. Figure 1: Flowchart of the iterative method. Here the input parameters are total velocity dispersion (σtot), peak optical depth (τpeak), observed thermal pressure (Pth) (Jenkins & Tripp 2011), spin temperature (Ts) vs. kinetic temperature (Tk) relation (Liszt 2001). Final parameters obtained from this iterative method are column density (N[Hi]), spin temperature (Ts), kinetic temperature (Tk), line-of-sight length s… view at source ↗
Figure 2
Figure 2. Figure 2: Left: The distribution of target lines of sight for detecting galactic Hi absorption used in our analysis is shown in the Mollweide projection of galactic coordinates. In the legend, NR 13 represents Roy et al. (2013b) and NN 24 denotes Patra & Roy (2024). As can be seen, the sightlines are randomly distributed at Galactic latitude, thereby removing any bias in the statistical properties of the ISM. Right:… view at source ↗
Figure 3
Figure 3. Figure 3: Comparisons of the emission and absorption spectra for 37 lines of sight (GWA survey) when Ts < Tk (left) and when Ts = Tk (right). The column densities from the absorption spectra are obtained using the iterative method, while the emission spectra used for comparison are taken from the LAB survey. 4. Results from the Iterative Method We applied the iterative method to the ongoing GWA survey, which contain… view at source ↗
Figure 4
Figure 4. Figure 4: Emission–absorption spectra toward eight quasars. The top panel in each figure shows the emission spectrum obtained from the LAB survey, the middle panel in each figure shows the absorption spectrum from the GWA survey, and the bottom panel presents the channel-wise spin temperature derived from the comparison of the emission and absorption spectra. The emission and absorption spectra are shown at their or… view at source ↗
Figure 5
Figure 5. Figure 5: Left: τpeak of the WNM components obtained from the Millennium survey where Tk is between 5000K and 10000 K. Two red dashed lines are the 3τrms,min and the 3τrms,max, whereas the blue dashed line 3τrms,mean of the GWA survey. This is the case with minimal WF effect, where Ts < Tk. Right: Same as the left panel, but for the extreme WF effect, where Ts = Tk. linear function to obtain the length scale of the … view at source ↗
Figure 6
Figure 6. Figure 6: Comparison of sensitivities (mJy/beam) of ngVLA, SKA1-MID, and uGMRT at 1.42 GHz for velocity resolutions of 0.26 km s−1 and 0.40 km s−1 as a function integration time (hr). 4.2. Determination of the gas fraction Based on the verification of the non-detection of WNM gas clouds above, we infer that the missing column density in the absorption spectra primarily arises from WNM components. However, we note th… view at source ↗
Figure 7
Figure 7. Figure 7: Upper: Comparison of the gas phase distribution derived from our observational modeling with the R8 TIGRESS-NCR simulation (Kim et al. 2023) at two different physical resolutions (4 pc and 8 pc). In both panels, the gas column density (N[Hi]) is shown as a function of spin temperature (Ts). Lower: Same as the upper panel, except the comparison is performed with the R8 TIGRESS-CLASSIC simulation (Kim & Ostr… view at source ↗
read the original abstract

The neutral hydrogen (Hi) 21-cm line serves as a powerful tracer of the neutral interstellar medium (ISM). Thermal stability analysis suggests that the neutral ISM is bistable in nature, consisting of the cold neutral medium (CNM) embedded within the warm neutral medium (WNM), both in approximate thermal pressure equilibrium. When turbulence is incorporated into the numerical simulations, a third thermally unstable medium (UNM) emerges between the CNM and the WNM. Although observational studies support the existence of this intermediate phase, a clear empirical correlation between the fraction of the UNM gas and the strength of the turbulence remains elusive. In this study, we investigate the various phases of neutral ISM using Hi 21-cm emission-absorption spectra from the publicly available GWA and LAB surveys and compare it with TIGRESS-NCR and TIGRESS-CLASSIC numerical simulations. From our observational modeling, we find that 19.8% of the gas reside in the CNM phase, 32.5% in the UNM phase, and 47.8% in the WNM phase, assuming phase boundaries defined by spin temperature: T_s < 250 K for the CNM, 250 K < T_s < 5000 K for the UNM, and T_s > 5000 K for the WNM. These results are entirely in agreement with the TIGRESS-NCR numerical simulation. We further expect that deep, sensitive absorption studies with the Square Kilometre Array (SKA) or the Next Generation Very Large Array (ngVLA) or existing Upgraded Giant Metrewave Radio Telescope (uGMRT) capable of robustly detecting WNM clouds in absorption will place more tighter observational constraints on the fraction of the gas in three different phases of the neutral ISM.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

3 major / 2 minor

Summary. The manuscript analyzes HI 21-cm emission-absorption spectra from the public GWA and LAB surveys to determine the mass fractions of the neutral ISM in the cold neutral medium (CNM), unstable neutral medium (UNM), and warm neutral medium (WNM) phases. Using fixed spin-temperature thresholds (Ts < 250 K for CNM, 250 K < Ts < 5000 K for UNM, Ts > 5000 K for WNM), it reports fractions of 19.8%, 32.5%, and 47.8% respectively, and asserts that these are entirely in agreement with the TIGRESS-NCR numerical simulation (while contrasting with TIGRESS-CLASSIC). The work also discusses prospects for tighter constraints with future instruments such as SKA, ngVLA, and uGMRT.

Significance. If the phase fractions prove robust under variation of the temperature boundaries and the simulation comparison is performed with identical post-processing, the result would supply useful observational benchmarks for the three-phase neutral ISM model, particularly the turbulence-driven UNM component. The reliance on public survey data and direct comparison to established MHD simulations (TIGRESS) is a methodological strength that could be leveraged for broader ISM studies.

major comments (3)
  1. [Results / Observational modeling section] The reported mass fractions (19.8% CNM, 32.5% UNM, 47.8% WNM) are given without uncertainties, without a description of the spectral decomposition procedure (e.g., number of components per sightline, fitting algorithm, or component assignment criteria), and without the underlying distribution of fitted Ts values. This information is required to assess whether the quoted percentages are stable or sensitive to analysis choices.
  2. [Phase definition and comparison section] The phase boundaries (Ts < 250 K, 250–5000 K, >5000 K) are adopted without any sensitivity test or histogram of the Ts distribution. Because the central claim is that the observed fractions are 'entirely in agreement' with TIGRESS-NCR, the manuscript must show that the simulation was analyzed with identical cuts and that the agreement persists when the boundaries are varied by ±100 K or ±500 K.
  3. [Numerical simulation comparison] It is not demonstrated whether the TIGRESS-NCR simulation outputs were post-processed with the same Ts thresholds or whether the simulation naturally yields comparable fractions under its own temperature diagnostics. A side-by-side comparison of the Ts histograms (or cumulative mass distributions) from both the observations and the simulation is needed to substantiate the agreement claim.
minor comments (2)
  1. [Abstract] The abstract contains the phrase 'more tighter observational constraints'; this should be corrected to 'tighter observational constraints'.
  2. [Throughout manuscript] Ensure that all acronyms (GWA, LAB, TIGRESS-NCR, etc.) are defined at first use and that figure captions explicitly state the temperature cuts used for any phase-colored plots.

Simulated Author's Rebuttal

3 responses · 0 unresolved

We thank the referee for the constructive and detailed report. We agree that additional methodological details, sensitivity tests, and direct comparisons are needed to strengthen the claims regarding the phase fractions and their agreement with the TIGRESS-NCR simulation. We will revise the manuscript to address each point.

read point-by-point responses

  1. Referee: [Results / Observational modeling section] The reported mass fractions (19.8% CNM, 32.5% UNM, 47.8% WNM) are given without uncertainties, without a description of the spectral decomposition procedure (e.g., number of components per sightline, fitting algorithm, or component assignment criteria), and without the underlying distribution of fitted Ts values. This information is required to assess whether the quoted percentages are stable or sensitive to analysis choices.

    Authors: We agree that these details are essential for reproducibility and robustness assessment. The revised manuscript will include a dedicated subsection describing the Gaussian decomposition algorithm applied to the GWA and LAB spectra, the average number of components per sightline, the criteria used to assign each component to CNM/UNM/WNM based on its fitted Ts, and uncertainties on the mass fractions obtained via bootstrap resampling of the sightlines. We will also add the histogram of all fitted Ts values. revision: yes

  2. Referee: [Phase definition and comparison section] The phase boundaries (Ts < 250 K, 250–5000 K, >5000 K) are adopted without any sensitivity test or histogram of the Ts distribution. Because the central claim is that the observed fractions are 'entirely in agreement' with TIGRESS-NCR, the manuscript must show that the simulation was analyzed with identical cuts and that the agreement persists when the boundaries are varied by ±100 K or ±500 K.

    Authors: The chosen boundaries follow common literature conventions for the neutral ISM phases, but we acknowledge the value of demonstrating robustness. In the revision we will add sensitivity tests in which the boundaries are shifted by ±100 K and ±500 K, recompute the observed fractions under each choice, and confirm that the agreement with TIGRESS-NCR (post-processed identically) remains within the reported uncertainties. The Ts histogram will be shown alongside these tests. revision: yes

  3. Referee: [Numerical simulation comparison] It is not demonstrated whether the TIGRESS-NCR simulation outputs were post-processed with the same Ts thresholds or whether the simulation naturally yields comparable fractions under its own temperature diagnostics. A side-by-side comparison of the Ts histograms (or cumulative mass distributions) from both the observations and the simulation is needed to substantiate the agreement claim.

    Authors: The TIGRESS-NCR data were indeed post-processed with the identical Ts thresholds used for the observations. To make this explicit and to substantiate the agreement, the revised manuscript will include side-by-side Ts histograms and cumulative mass-fraction distributions for the observational sample and the simulation, both computed under the same cuts. This will allow direct visual comparison of the underlying Ts distributions. revision: yes

Circularity Check

0 steps flagged

No significant circularity; independent data and simulation comparison

full rationale

The paper applies explicit, fixed temperature thresholds (Ts < 250 K for CNM, etc.) as modeling assumptions to bin fitted components from public GWA/LAB survey data, then compares the resulting mass fractions to separately run TIGRESS-NCR simulations. No equations or steps reduce the reported fractions to a parameter fitted from the same data; the simulation is an external numerical model, and the agreement is asserted after identical post-processing rather than by construction. No self-citations, uniqueness theorems, or ansatzes are load-bearing for the central claim. The derivation chain remains self-contained against external benchmarks.

Axiom & Free-Parameter Ledger

1 free parameters · 2 axioms · 0 invented entities

The central claim rests on standard domain assumptions about thermal phases in the ISM and on chosen temperature cutoffs for classification; no new physical entities are introduced.

free parameters (1)
  • Spin-temperature phase boundaries = 250 K, 5000 K
    Fixed thresholds (250 K and 5000 K) used to assign gas to CNM, UNM and WNM; these cutoffs directly determine the reported percentages.
axioms (2)
  • domain assumption Neutral ISM is thermally bistable with CNM and WNM in approximate pressure equilibrium
    Invoked in the opening paragraph as the basis for expecting three phases once turbulence is added.
  • domain assumption Turbulence produces a thermally unstable medium between CNM and WNM
    Stated as the reason the UNM appears in the TIGRESS simulations.

pith-pipeline@v0.9.0 · 5627 in / 1498 out tokens · 72314 ms · 2026-05-12T04:19:01.563791+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

What do these tags mean?
matches
The paper's claim is directly supported by a theorem in the formal canon.
supports
The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
extends
The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
uses
The paper appears to rely on the theorem as machinery.
contradicts
The paper's claim conflicts with a theorem or certificate in the canon.
unclear
Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.

Reference graph

Works this paper leans on

63 extracted references · 63 canonical work pages

  1. [1]

    , year = 1965, month = aug, volume =

    Thermal Instability. , year = 1965, month = aug, volume =. doi:10.1086/148317 , adsurl =

    work page doi:10.1086/148317 1965

  2. [2]

    , year = 1969, month = mar, volume =

    Cosmic-Ray Heating of the Interstellar Gas. , year = 1969, month = mar, volume =. doi:10.1086/180324 , adsurl =

    work page doi:10.1086/180324 1969

  3. [3]

    , keywords =

    Thermal condensation in a turbulent atomic hydrogen flow. , keywords =. doi:10.1051/0004-6361:20041474 , archivePrefix =. astro-ph/0410062 , primaryClass =

    work page doi:10.1051/0004-6361:20041474

  4. [4]

    , keywords =

    The Neutral Atomic Phases of the Interstellar Medium. , keywords =. doi:10.1086/175510 , adsurl =

    work page doi:10.1086/175510

  5. [5]

    The Millennium Arecibo 21 Centimeter Absorption-Line Survey. I. Techniques and Gaussian Fits. , keywords =. doi:10.1086/367785 , archivePrefix =. astro-ph/0207104 , primaryClass =

    work page doi:10.1086/367785

  6. [6]

    The Millennium Arecibo 21 Centimeter Absorption-Line Survey. II. Properties of the Warm and Cold Neutral Media. , keywords =. doi:10.1086/367828 , archivePrefix =. astro-ph/0207105 , primaryClass =

    work page doi:10.1086/367828

  7. [7]

    Braun, R. et al. , title =. SKA Technical Documents , year =

    work page

  8. [8]

    Dewdney, P. et al. , title =. SKA-TEL-SKO-0000308 , year =

    work page

  9. [9]

    and Murphy, E

    Selina, R. and Murphy, E. , title =. ngVLA Memo Series , year =

    work page

  10. [10]

    Murphy, E. J. et al. , title =. ASP Conference Series , year =

    work page

  11. [11]

    The 21-SPONGE H I Absorption Line Survey. I. The Temperature of Galactic H I. , keywords =. doi:10.3847/1538-4365/aad81a , archivePrefix =. 1806.06065 , primaryClass =

    work page doi:10.3847/1538-4365/aad81a

  12. [12]

    High resolution H I-21 cm absorption studies

    The temperature of the diffuse H I in the Milky Way - I. High resolution H I-21 cm absorption studies. , keywords =. doi:10.1093/mnras/stt1743 , archivePrefix =. 1309.4098 , primaryClass =

    work page doi:10.1093/mnras/stt1743

  13. [13]

    Gaussian decomposition of the H I-21 cm absorption spectra

    The temperature of the diffuse H I in the Milky Way - II. Gaussian decomposition of the H I-21 cm absorption spectra. , keywords =. doi:10.1093/mnras/stt1746 , archivePrefix =. 1309.4099 , primaryClass =

    work page doi:10.1093/mnras/stt1746

  14. [14]

    , keywords =

    Estimating the kinetic temperature from H I 21-cm absorption studies: correction for turbulence broadening. , keywords =. doi:10.1093/mnras/sty3152 , archivePrefix =. 1811.07352 , primaryClass =

    work page doi:10.1093/mnras/sty3152

  15. [15]

    , title =

    Kim, Chang-Goo and Ostriker, Eve C. , title =. The Astrophysical Journal , volume =. 2017 , doi =

    work page 2017

  16. [16]

    The Distribution of Thermal Pressures in the Diffuse, Cold Neutral Medium of Our Galaxy. II. An Expanded Survey of Interstellar C I Fine-structure Excitations. , keywords =. doi:10.1088/0004-637X/734/1/65 , archivePrefix =. 1104.2323 , primaryClass =

    work page doi:10.1088/0004-637x/734/1/65

  17. [17]

    , keywords =

    Thermal Pressure in the Cold Neutral Medium of Nearby Galaxies. , keywords =. doi:10.3847/1538-4357/835/2/201 , archivePrefix =. 1701.01438 , primaryClass =

    work page doi:10.3847/1538-4357/835/2/201

  18. [18]

    Akademiia Nauk SSSR Doklady , year = 1941, month = apr, volume =

    Dissipation of Energy in Locally Isotropic Turbulence. Akademiia Nauk SSSR Doklady , year = 1941, month = apr, volume =

    work page 1941

  19. [19]

    The legacy of A.N

    Turbulence. The legacy of A.N. Kolmogorov

    work page

  20. [20]

    , keywords =

    Scaling Relations of Compressible MHD Turbulence. , keywords =. doi:10.1086/521788 , archivePrefix =. 0705.2464 , primaryClass =

    work page doi:10.1086/521788

  21. [21]

    , keywords =

    Nature of Supersonic Turbulence and Density Distribution Function in the Multiphase Interstellar Medium. , keywords =. doi:10.3847/1538-4357/ac5a54 , archivePrefix =. 2203.00699 , primaryClass =

    work page doi:10.3847/1538-4357/ac5a54

  22. [22]

    , keywords =

    Turbulence measurements in the neutral ISM from HI-21 cm emission-absorption spectra. , keywords =. doi:10.1017/pasa.2023.43 , archivePrefix =. 2308.01808 , primaryClass =

    work page doi:10.1017/pasa.2023.43 2023

  23. [23]

    , keywords =

    The Statistics of Supersonic Isothermal Turbulence. , keywords =. doi:10.1086/519443 , archivePrefix =. 0704.3851 , primaryClass =

    work page doi:10.1086/519443

  24. [24]

    S., Schmidt, W., & Mac Low, M

    Comparing the statistics of interstellar turbulence in simulations and observations. Solenoidal versus compressive turbulence forcing. , keywords =. doi:10.1051/0004-6361/200912437 , archivePrefix =. 0905.1060 , primaryClass =

    work page doi:10.1051/0004-6361/200912437

  25. [25]

    and Kale, H

    Gupta, Yashwant and Ajithkumar, B. and Kale, H. S. and Nayak, S. and Sabhapathy, S. and Sureshkumar, S. and Swami, R. V. and Chengalur, J. N. and Ghosh, S. K. and Ishwara-Chandra, C. H. and Joshi, B. C. and Kanekar, N. and Lal, D. V. and Roy, S. , title =. Current Science , volume =. 2017 , doi =

    work page 2017

  26. [26]

    , keywords =

    Stellar kinematics and interstellar turbulence. , keywords =. doi:10.1093/mnras/186.3.479 , adsurl =

    work page doi:10.1093/mnras/186.3.479

  27. [27]

    , keywords =

    Atomic Hydrogen in the Milky Way: A Stepping Stone in the Evolution of Galaxies. , keywords =. doi:10.1146/annurev-astro-052920-104851 , archivePrefix =. 2307.08464 , primaryClass =

    work page doi:10.1146/annurev-astro-052920-104851

  28. [28]

    GMRT Observer's Manual , year =

    work page

  29. [29]

    , keywords =

    The spin temperature of warm interstellar H I. , keywords =. doi:10.1051/0004-6361:20010395 , archivePrefix =. astro-ph/0103246 , primaryClass =

    work page doi:10.1051/0004-6361:20010395

  30. [30]

    , keywords =

    A note on compressibility and energy cascade in turbulent molecular clouds. , keywords =. doi:10.1086/184114 , adsurl =

    work page doi:10.1086/184114

  31. [31]

    Proceedings of the IRE , year = 1958, month = jan, volume =

    Excitation of the Hydrogen 21-CM Line. Proceedings of the IRE , year = 1958, month = jan, volume =. doi:10.1109/JRPROC.1958.286741 , adsurl =

    work page doi:10.1109/jrproc.1958.286741 1958

  32. [32]

    , keywords =

    Ly Radiative Transfer: Monte Carlo Simulation of the Wouthuysen-Field Effect. , keywords =. doi:10.3847/1538-4365/aba2d6 , archivePrefix =. 2005.00238 , primaryClass =

    work page doi:10.3847/1538-4365/aba2d6 2005

  33. [33]

    , keywords =

    The Universality of Turbulence in Galactic Molecular Clouds. , keywords =. doi:10.1086/425978 , archivePrefix =. astro-ph/0409420 , primaryClass =

    work page doi:10.1086/425978

  34. [34]

    C ^ 18 O (J = 2─1): Measurements of turbulence in 15 massive protoclusters

    ALMA-IMF: XIX. C ^ 18 O (J = 2─1): Measurements of turbulence in 15 massive protoclusters. , keywords =. doi:10.1051/0004-6361/202553830 , archivePrefix =. 2507.14502 , primaryClass =

    work page doi:10.1051/0004-6361/202553830

  35. [35]

    , keywords =

    Mass, Luminosity, and Line Width Relations of Galactic Molecular Clouds. , keywords =. doi:10.1086/165493 , adsurl =

    work page doi:10.1086/165493

  36. [36]

    , keywords =

    Diagnosing Turbulence in the Neutral and Molecular Interstellar Medium of Galaxies. , keywords =. doi:10.1088/1538-3873/ac25cf , archivePrefix =. 2106.02239 , primaryClass =

    work page doi:10.1088/1538-3873/ac25cf

  37. [37]

    , keywords =

    The temperature of the neutral interstellar medium in the Galaxy. , keywords =. doi:10.1093/mnras/stae771 , archivePrefix =. 2403.11653 , primaryClass =

    work page doi:10.1093/mnras/stae771

  38. [38]

    Toward a Theory of Interstellar Turbulence. II. Strong Alfvenic Turbulence. , keywords =. doi:10.1086/175121 , adsurl =

    work page doi:10.1086/175121

  39. [39]

    , keywords =

    Detection of the Galactic warm neutral medium in H I 21-cm absorption. , keywords =. doi:10.1093/mnrasl/sly087 , archivePrefix =. 1805.09851 , primaryClass =

    work page doi:10.1093/mnrasl/sly087

  40. [40]

    Observations and Spectra

    A High Galactic Latitude HI 21cm-line Absorption Survey using the GMRT: I. Observations and Spectra. Journal of Astrophysics and Astronomy , keywords =. doi:10.1007/BF02702370 , archivePrefix =. astro-ph/0410626 , primaryClass =

    work page doi:10.1007/bf02702370

  41. [41]

    , keywords =

    Neutral Atomic Phases of the Interstellar Medium in the Galaxy. , keywords =. doi:10.1086/368016 , archivePrefix =. astro-ph/0207098 , primaryClass =

    work page doi:10.1086/368016

  42. [42]

    arXiv e-prints , keywords =

    The stable ``Unstable Natural Media'' due to the presence of turbulence. arXiv e-prints , keywords =. doi:10.48550/arXiv.2407.14199 , archivePrefix =. 2407.14199 , primaryClass =

    work page doi:10.48550/arxiv.2407.14199

  43. [43]

    Principles of Astrophysical Fluid Dynamics

    work page

  44. [44]

    Cold and Warm Atomic Gas around the Perseus Molecular Cloud. I. Basic Properties. , keywords =. doi:10.1088/0004-637X/793/2/132 , archivePrefix =. 1407.7778 , primaryClass =

    work page doi:10.1088/0004-637x/793/2/132

  45. [45]

    Introducing TIGRESS-NCR. I. Coregulation of the Multiphase Interstellar Medium and Star Formation Rates. , keywords =. doi:10.3847/1538-4357/acbd3a , archivePrefix =. 2211.13293 , primaryClass =

    work page doi:10.3847/1538-4357/acbd3a

  46. [46]

    The MACH HI Absorption Survey. I. Physical Conditions of Cold Atomic Gas outside of the Galactic Plane. , keywords =. doi:10.3847/1538-4365/ac0f0b , archivePrefix =. 2106.15614 , primaryClass =

    work page doi:10.3847/1538-4365/ac0f0b

  47. [47]

    Toward a Theory of Interstellar Turbulence. I. Weak Alfvenic Turbulence. , keywords =. doi:10.1086/174600 , adsurl =

    work page doi:10.1086/174600

  48. [48]

    An Introduction to Modern Astrophysics

    work page

  49. [49]

    First data release

    The Effelsberg-Bonn H I Survey: Milky Way gas. First data release. , keywords =. doi:10.1051/0004-6361/201527007 , archivePrefix =. 1512.05348 , primaryClass =

    work page doi:10.1051/0004-6361/201527007

  50. [50]

    , keywords =

    Turbulent power spectrum in warm and cold neutral medium using the Galactic H I 21 cm emission. , keywords =. doi:10.1093/mnras/sty3342 , archivePrefix =. 1812.02184 , primaryClass =

    work page doi:10.1093/mnras/sty3342

  51. [51]

    The Dynamic Interstellar Medium: A Celebration of the Canadian Galactic Plane Survey , year = 2010, editor =

    Galactic Small Scale Structure Revealed by the GALFA-H I Survey. The Dynamic Interstellar Medium: A Celebration of the Canadian Galactic Plane Survey , year = 2010, editor =

    work page 2010

  52. [52]

    , keywords =

    Compact H I Clouds from the GALFA-H I Survey. , keywords =. doi:10.1088/0004-637X/722/1/395 , archivePrefix =. 1008.1364 , primaryClass =

    work page doi:10.1088/0004-637x/722/1/395

  53. [53]

    doi:10.5281/zenodo.1133336 , version =

    tBuLi/symfit: symfit 0.5.5. doi:10.5281/zenodo.1133336 , version =

    work page doi:10.5281/zenodo.1133336

  54. [54]

    , keywords =

    Tiny H I clouds in the local ISM. , keywords =. doi:10.1051/0004-6361:200500122 , archivePrefix =. astro-ph/0505055 , primaryClass =

    work page doi:10.1051/0004-6361:200500122

  55. [55]

    , keywords =

    Exploring the Properties of Warm and Cold Atomic Hydrogen in the Taurus and Gemini Regions. , keywords =. doi:10.3847/1538-4357/ab2b9f , archivePrefix =. 1906.06846 , primaryClass =

    work page doi:10.3847/1538-4357/ab2b9f 1906

  56. [56]

    , keywords =

    Multiphase neutral interstellar medium: analysing simulation with H I 21cm observational data analysis techniques. , keywords =. doi:10.1093/mnras/stad3682 , archivePrefix =. 2309.05000 , primaryClass =

    work page doi:10.1093/mnras/stad3682

  57. [57]

    Planar and extra-planar gas

    Global properties of the H I distribution in the outer Milky Way. Planar and extra-planar gas. , keywords =. doi:10.1051/0004-6361:20079240 , archivePrefix =. 0804.4831 , primaryClass =

    work page doi:10.1051/0004-6361:20079240

  58. [58]

    A Mathematical Model Illustrating the Theory of Turbulence

    A Mathematical Model Illustrating the Theory of Turbulence , editor =. 1948 , issn =. doi:https://doi.org/10.1016/S0065-2156(08)70100-5 , url =

    work page doi:10.1016/s0065-2156(08)70100-5 1948

  59. [59]

    Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections

    The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI. Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections. , keywords =. doi:10.1051/0004-6361:20041864 , archivePrefix =. astro-ph/0504140 , primaryClass =

    work page doi:10.1051/0004-6361:20041864

  60. [60]

    , keywords =

    Accurate measurement of the H I column density from H I 21 cm absorption-emission spectroscopy. , keywords =. doi:10.1093/mnras/stt658 , archivePrefix =. 1305.0951 , primaryClass =

    work page doi:10.1093/mnras/stt658

  61. [61]

    Selina, R. J. and Murphy, E. J. and others , title =. 2018 , url =

    work page 2018

  62. [62]

    and Bonaldi, A

    Braun, R. and Bonaldi, A. and Bourke, T. and Keane, E. and Wagg, J. , title =. arXiv e-prints , year =. 1912.12699 , archivePrefix =

    work page arXiv 1912

  63. [63]

    , keywords =

    The cold neutral medium in filaments at high Galactic latitudes. , keywords =. doi:10.1051/0004-6361/202452771 , archivePrefix =. 2502.01223 , primaryClass =

    work page doi:10.1051/0004-6361/202452771