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The Atomic-to-Molecular Transition in Galaxies. III. A New Method for Determining the Molecular Content of Primordial and Dusty Clouds

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Paper breakdownThe authors' claims, conditions and measurements, as JSON Signed receiptProof this review has not been altered
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Christopher F. McKee, Mark R. Krumholz

Astrophysics of Galaxies · Submitted 3 Aug 2009

abstract compiled · 2026-09-23 · no language-model review

The authors' main claim We present simple, accurate analytic fits to our results that are suitable for comparison to observations and to implementation in numerical and semi-analytic models.

how it is stated · asserted 1.00 read the record →

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arXiv ID0908.0330 (version 2)
Pith IDMYHMK7P2, Pith's permanent record of this paper and its review
CitationChristopher F. McKee, Mark R. Krumholz. "The Atomic-to-Molecular Transition in Galaxies. III. A New Method for Determining the Molecular Content of Primordial and Dusty Clouds." arXiv:0908.0330 (2009). https://pith.science/paper/MYHMK7P2
Claim paper

The compiled record

The paper's own sentences, arranged. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.

Open the compiled record

Compiled by classifier-1.13-20260917 via OpenRouter, question bank abstract-p1-20260923, 2026-09-23: 1 request, 5,579 input tokens, $0.0002 reported.

What the abstract itself states, as probabilities: claims first 0.10 · states limitation 0.75 · human participants 0.01 · controlled comparison 0.22 · randomized assignment 0.01 · states quantitative result 0.94 · compares with prior results 0.98 · mentions code or data availability 0.03.

The abstract, sentence by sentence

arXiv listing abstract v2. Results and the main claim are underlined; .

Understanding the molecular content of galaxies is a critical problem in star formation and galactic evolution. Here we present a new method, based on a Stromgren-type analysis, to calculate the amount of HI that surrounds a molecular cloud irradiated by an isotropic radiation field. We consider both planar and spherical clouds, and H_2 formation either in the gas phase or catalyzed by dust grains. Under the assumption that the transition from atomic to molecular gas is sharp, our method gives the solution without any reference to the photodissociation cross section. We test our results for the planar case against those of a PDR code, and find typical accuracies of about 10%. Our results are also consistent with the scaling relations found in Paper I of this series, but they apply to a wider range of physical conditions. We present simple, accurate analytic fits to our results that are suitable for comparison to observations and to implementation in numerical and semi-analytic models.

background contribution method result interpretation main claim

What the classifier reports for each sentence. The number is the probability it gave the label.
#sentencerolethe authors' own workstates the main conclusionstrength
s0 Understanding the molecular content of galaxies is a critical problem in star formation and galactic evolution. background 1.00 0.04 0.03 asserted 1.00
s1 Here we present a new method, based on a Stromgren-type analysis, to calculate the amount of HI that surrounds a molecular cloud irradiated by an isotropic radiation field. contribution 0.72 0.94 0.21 asserted 0.99
s2 We consider both planar and spherical clouds, and H_2 formation either in the gas phase or catalyzed by dust grains. method 0.91 0.76 0.03 asserted 0.79
s3 Under the assumption that the transition from atomic to molecular gas is sharp, our method gives the solution without any reference to the photodissociation cross section. method 0.43 0.85 0.25 asserted 0.96
s4 We test our results for the planar case against those of a PDR code, and find typical accuracies of about 10%. result 0.77 0.97 0.08 asserted 1.00
s5 Our results are also consistent with the scaling relations found in Paper I of this series, but they apply to a wider range of physical conditions. result 0.62 0.75 0.13 hedged possibility 0.71
s6 We present simple, accurate analytic fits to our results that are suitable for comparison to observations and to implementation in numerical and semi-analytic models. contribution 0.73 0.94 0.28 asserted 1.00

What kind of paper the classifier reports this is: method or tool 1.00 · evidence from proof or derivation 0.90.

What was examined, and what was not

sources read
  • arXiv listing abstract v2
not examined
  • full text
  • figures and tables
  • references and citing sentences
  • relations to other papers
levels run
  • P abstract
not run
  • S sections
  • T body sentences
  • C citations
  • R cross-paper relations

Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. Every number in the measurements table is the authors', checked by code. Record as JSON

The paper
Original abstract

Understanding the molecular content of galaxies is a critical problem in star formation and galactic evolution. Here we present a new method, based on a Stromgren-type analysis, to calculate the amount of HI that surrounds a molecular cloud irradiated by an isotropic radiation field. We consider both planar and spherical clouds, and H_2 formation either in the gas phase or catalyzed by dust grains. Under the assumption that the transition from atomic to molecular gas is sharp, our method gives the solution without any reference to the photodissociation cross section. We test our results for the planar case against those of a PDR code, and find typical accuracies of about 10%. Our results are also consistent with the scaling relations found in Paper I of this series, but they apply to a wider range of physical conditions. We present simple, accurate analytic fits to our results that are suitable for comparison to observations and to implementation in numerical and semi-analytic models.

Human review

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References
How later papers used it

48 later papers cite it

Evidence: substantial. 42 of the citing papers share no author with it, and 20 of those carry a confident label from Pith's citation classifier.

Pith read 15 of the 56 citing sentences, choosing only those whose citation markers point at this paper alone, and wrote the paraphrases from them. The summary, the counts, the evidence level, the links and the quotes come from code; the summary counts the papers listed below. A later paper is listed under a label when Pith's citation classifier gives one of its sentences that label at probability 0.8 or more (0.95 for support), Pith's reading finds that the citing paper itself did it, and a second check confirms the paraphrase against the sentence. This section lists uses only. It does not list criticism or disagreement, so their absence here says nothing about how the paper has been received. Papers that share an author with this one are listed apart, under "By the same authors". A quote is the citing authors' own sentence, shown when their paper's licence is CC BY, CC BY-SA or CC0. JSON

Uses its method or tool 6 of 17 papers with this label
Uses its data or values 1 of 2 papers with this label
How the literature uses it

3 arXiv papers cite this in 3 sentences

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

Papers citing it · 2 sentences without a confident label

Uses its method or tool 1 paper
  • As in Ref. [ref] , we use the Krumholz-McKee-Tumlinson (KMT) model [ref] to determine the fraction $f_H_2$ of all neutral Hydrogen that is molecular: f_H_2= 1 - 0.75s/(1 + 0.25s) if s < 2 0 if s ≥2 or gas is non-star-forming, with s = ln(1 + 0.6χ+ 0.01χ^2)/0.6τ_c, χ = 0.756(1 + 3.1Z^0.365), τ_c = 3/4Σ_gas σ_d/μ_H, and where $Z$ is the gas metalicity in solar units, $σ_d = Z×10^-21 cm^2$ is an estimate of the cross-section of dust, $μ_H$ is the mean hydrogen nucleus mass and $Σ_gas$ is the gas surface density.

    The local PNG bias of neutral Hydrogen, ${\rm H_I}$ · Modeling of $$ · 1.00

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