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Non-equilibrium H2 ortho-to-para ratio in two molecular clouds of the Galactic Center

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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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N. J. Rodriguez-Fernandez, J. Martin-Pintado, P. de Vicente, A. Fuente, S. Huettemeister, T. L. Wilson, D. Kunze

Astrophysics · Submitted 25 Feb 2000

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

The authors' main claim Low velocity shocks (~ 10 km/s) are the most likely explanation for the column densities of warm gas and dust and the non-LTE H2 OTPR.

how it is stated · hedged possibility 0.98 read the record →

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arXiv IDastro-ph/0002478 (version 1)
Pith IDYCYJFIKU, Pith's permanent record of this paper and its review
CitationA. Fuente, D. Kunze, J. Martin-Pintado, N. J. Rodriguez-Fernandez, P. de Vicente, S. Huettemeister, T. L. Wilson. "Non-equilibrium H2 ortho-to-para ratio in two molecular clouds of the Galactic Center." arXiv:astro-ph/0002478 (2000). https://pith.science/paper/YCYJFIKU
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.

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Compiled by classifier-1.13.0 via TypeSafe API, question bank abstract-p1-20260923, 2026-09-23: 1 request, 6,438 input tokens.

What the abstract itself states, as probabilities: claims first 0.90 · states limitation 0.28 · human participants 0.02 · controlled comparison 0.17 · randomized assignment 0.01 · states quantitative result 0.99 · compares with prior results 0.88 · mentions code or data availability 0.02.

The abstract, sentence by sentence

arXiv listing abstract v1. Results and the main claim are underlined; .

We present ISO observations of the S(0), S(1), S(2), and S(3) rotational lines of molecular hydrogen from two molecular clouds near the Galactic Center (GC). We have also measured continuum dust emission at infrared wavelengths with ISO and the rotational radio lines J=1-0 of 13CO and C18O and J=2-1 of C18O with the IRAM-30m telescope. Using the dust continuum spectra and the CO lines we derive a total visual extinction of 15-20 magnitudes toward these GC clouds. After correcting the H2 data for extinction, the gas temperatures are \~250 K and the column densities of warm gas are ~2e21 cm-2. This is the first direct measure of the H2 column densities of the warm component; with this, we estimate an NH3 abundance in the warm gas of ~ 2e-7. The column density of warm gas is, at least, a factor of 100 larger than the corresponding column densities derived from the warm dust. The observed ortho-to-para ratio (OTPR) is ~ 1, clearly below the local thermodynamical equilibrium (LTE) OTPR for gas at 250 K of ~3. Low velocity shocks (~ 10 km/s) are the most likely explanation for the column densities of warm gas and dust and the non-LTE H2 OTPR.

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 We present ISO observations of the S(0), S(1), S(2), and S(3) rotational lines of molecular hydrogen from two molecular clouds near the Galactic Center (GC). contribution 0.87 0.97 0.03 asserted 0.99
s1 We have also measured continuum dust emission at infrared wavelengths with ISO and the rotational radio lines J=1-0 of 13CO and C18O and J=2-1 of C18O with the IRAM-30m telescope. method 0.98 0.96 0.02 asserted 1.00
s2 Using the dust continuum spectra and the CO lines we derive a total visual extinction of 15-20 magnitudes toward these GC clouds. result 0.94 0.95 0.04 asserted 1.00
s3 After correcting the H2 data for extinction, the gas temperatures are \~250 K and the column densities of warm gas are ~2e21 cm-2. result 1.00 0.95 0.07 asserted 1.00
s4 This is the first direct measure of the H2 column densities of the warm component; with this, we estimate an NH3 abundance in the warm gas of ~ 2e-7. result 0.93 0.92 0.09 asserted 0.98
s5 The column density of warm gas is, at least, a factor of 100 larger than the corresponding column densities derived from the warm dust. result 0.98 0.89 0.12 asserted 0.96
s6 The observed ortho-to-para ratio (OTPR) is ~ 1, clearly below the local thermodynamical equilibrium (LTE) OTPR for gas at 250 K of ~3. result 1.00 0.94 0.40 asserted 1.00
s7 Low velocity shocks (~ 10 km/s) are the most likely explanation for the column densities of warm gas and dust and the non-LTE H2 OTPR. interpretation 1.00 0.59 0.76 hedged possibility 0.98

What kind of paper the classifier reports this is: empirical study 1.00 · evidence from observation or experiment 1.00.

What was examined, and what was not

sources read
  • arXiv listing abstract v1
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

We present ISO observations of the S(0), S(1), S(2), and S(3) rotational lines of molecular hydrogen from two molecular clouds near the Galactic Center (GC). We have also measured continuum dust emission at infrared wavelengths with ISO and the rotational radio lines J=1-0 of 13CO and C18O and J=2-1 of C18O with the IRAM-30m telescope. Using the dust continuum spectra and the CO lines we derive a total visual extinction of 15-20 magnitudes toward these GC clouds. After correcting the H2 data for extinction, the gas temperatures are \~250 K and the column densities of warm gas are ~2e21 cm-2. This is the first direct measure of the H2 column densities of the warm component; with this, we estimate an NH3 abundance in the warm gas of ~ 2e-7. The column density of warm gas is, at least, a factor of 100 larger than the corresponding column densities derived from the warm dust. The observed ortho-to-para ratio (OTPR) is ~ 1, clearly below the local thermodynamical equilibrium (LTE) OTPR for gas at 250 K of ~3. Low velocity shocks (~ 10 km/s) are the most likely explanation for the column densities of warm gas and dust and the non-LTE H2 OTPR.

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2 arXiv papers cite this in 2 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

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