Cosmology and Nongalactic Astrophysics · arXiv:1305.0277 v1 · submitted 1 May 2013
ALFALFA Discovery of the Nearby Gas-Rich Dwarf Galaxy Leo P. III. An Extremely Metal Deficient Galaxy
The paper says
“Thus, Leo P is an extremely metal deficient (XMD) galaxy, and, indeed, one of the most metal deficient star-forming galaxies ever observed.”
from the abstract · picked out as the main claim by a classifier
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The paper
Abstract
We present KPNO 4-m and LBT/MODS spectroscopic observations of an HII region in the nearby dwarf irregular galaxy Leo P discovered recently in the Arecibo ALFALFA survey. In both observations, we are able to accurately measure the temperature sensitive [O III] 4363 Angstrom line and determine a "direct" oxygen abundance of 12 + log(O/H) = 7.17 +/- 0.04. Thus, Leo P is an extremely metal deficient (XMD) galaxy, and, indeed, one of the most metal deficient star-forming galaxies ever observed. For its estimated luminosity, Leo P is consistent with the relationship between luminosity and oxygen abundance seen in nearby dwarf galaxies. Leo P shows normal alpha element abundance ratios (Ne/O, S/O, and Ar/O) when compared to other XMD galaxies, but elevated N/O, consistent with the "delayed release" hypothesis for N/O abundances. We derive a helium mass fraction of 0.2509 +0.0184 -0.0123 which compares well with the WMAP + BBN prediction of 0.2483 +/- 0.0002 for the primordial helium abundance. We suggest that surveys of very low mass galaxies compete well with emission line galaxy surveys for finding XMD galaxies. It is possible that XMD galaxies may be divided into two classes: the relatively rare XMD emission line galaxies which are associated with starbursts triggered by infall of low-metallicity gas and the more common, relatively quiescent XMD galaxies like Leo P, with very low chemical abundances due to their intrinsically small masses.
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. No sentence in this record was written by a model.
abstract compiled · 2026-09-23 · no language-model review
How the main claim is stated: asserted 1.00
What the abstract itself states, as probabilities: claims first 0.05 · states limitation 0.14 · human participants 0.01 · controlled comparison 0.34 · randomized assignment 0.01 · states quantitative result 0.99 · compares with prior results 0.92 · mentions code or data availability 0.02
The abstract, sentence by sentence
This table labels the abstract only (arXiv listing abstract v1). The number is the probability the classifier gave the label.
| Sentence | Role | The authors' own work | States the main conclusion | Strength |
|---|---|---|---|---|
| We present KPNO 4-m and LBT/MODS spectroscopic observations of an HII region in the nearby dwarf irregular galaxy Leo P discovered recently in the Arecibo ALFALFA survey. | contribution 0.70 | 0.94 | 0.03 | asserted 0.99 |
| In both observations, we are able to accurately measure the temperature sensitive [O III] 4363 Angstrom line and determine a "direct" oxygen abundance of 12 + log(O/H) = 7.17 +/- 0.04. | result 0.98 | 0.98 | 0.10 | asserted 1.00 |
| Thus, Leo P is an extremely metal deficient (XMD) galaxy, and, indeed, one of the most metal deficient star-forming galaxies ever observed. | interpretation 0.73 | 0.87 | 0.73 | asserted 1.00 |
| For its estimated luminosity, Leo P is consistent with the relationship between luminosity and oxygen abundance seen in nearby dwarf galaxies. | result 0.77 | 0.68 | 0.07 | hedged possibility 0.86 |
| Leo P shows normal alpha element abundance ratios (Ne/O, S/O, and Ar/O) when compared to other XMD galaxies, but elevated N/O, consistent with the "delayed release" hypothesis for N/O abundances. | result 0.93 | 0.89 | 0.07 | asserted 0.96 |
| We derive a helium mass fraction of 0.2509 +0.0184 -0.0123 which compares well with the WMAP + BBN prediction of 0.2483 +/- 0.0002 for the primordial helium abundance. | result 0.99 | 0.96 | 0.08 | asserted 0.94 |
| We suggest that surveys of very low mass galaxies compete well with emission line galaxy surveys for finding XMD galaxies. | interpretation 0.55 | 0.30 | 0.20 | hedged possibility 0.88 |
| It is possible that XMD galaxies may be divided into two classes: the relatively rare XMD emission line galaxies which are associated with starbursts triggered by infall of low-metallicity gas and the more common, relatively quiescent XMD galaxies like Leo P, with very low chemical abundances due to their intrinsically small masses. | interpretation 1.00 | 0.19 | 0.22 | hedged possibility 0.97 |
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
How the labels were made
Compiled by classifier-1.13-20260917 via OpenRouter, question bank abstract-p1-20260923, 2026-09-23: 1 request, 6,602 input tokens, $0.0003 reported.
Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. This record as JSON
Cited by 4 Pith papers
Reviewed papers on Pith that cite this one. OpenAlex reports about 150 citations worldwide. The full citation record
- Strong constraints on decay and annihilation of dark matter from heating of gas-rich dwarf galaxies hep-ph · Nov 2021
- Fifty years of primordial helium abundances: A statistical reanalysis astro-ph.CO · Jun 2026
- Improving Helium Abundance Determinations with Leo P as a Case Study astro-ph.CO · Oct 2020
- The primordial helium abundance from updated emissivities astro-ph.CO · Aug 2013
How the literature uses it
5 arXiv papers cite this in 14 sentences
Papers citing it · 7 sentences without a confident label
Uses its method or tool 1 paper
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As in [ref] , the uncertainties on the flux measurements were approximated using [equation] where $N$ is the number of pixels spanning the Gaussian profile fit to the narrow emission lines and $ζ$ is the rms noise in the continuum determined as the average of the rms measured on each side of an emission line.
Improving Helium Abundance Determinations with Leo P as a Case Study · Re-Analysis of the LBT/MODS Spectrum · 0.98
Uses its data or values 3 papers
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The O/H values are taken directly from [ref] , except for Leo P, where the value is taken from [ref] .
Improving Helium Abundance Determinations with Leo P as a Case Study · The Primordial Helium Abundance · 0.98
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Finally, we also include analysis of the recently discovered extremely metal deficient dwarf galaxy Leo P [ref] .
The primordial helium abundance from updated emissivities · Results from the Final Dataset · 0.90
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For Leo P, however, a HII region has been detected and the gas metal abundance derived from oxygen lines is $10^-1.75$ [ref] .
Strong constraints on decay and annihilation of dark matter from heating of gas-rich dwarf galaxies · Leo T gas metal abundances · 0.97
Compares with it 1 paper
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The best-fit model parameter values and uncertainties are given in table [ref], with comparison to the previous analysis from [ref] .
Improving Helium Abundance Determinations with Leo P as a Case Study · Leo P · 0.82
What it cites · 1 sentence without a confident label
Contests 1 paper
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Unfortunately, an error has been discovered in the new emissivities [ref] .
Corrigendum: Improved He~I Emissivities in the Case B Approximation · The He Abundance of Leo P from LBT/MODS · contest 0.93
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