The distances of supernova remnants Kes 69 and G21.5–0.9 from H<scp>i</scp> and 13CO spectra
Bibliographic record
Abstract
Abstract We obtain new H i and 13CO images around supernova remnants Kes 69 and G21.5–0.9. By comparing H i spectra with 13CO emission spectra, we significantly revise the kinematic distance for Kes 69 to ∼5.5 kpc, which was 11.2 kpc, and refine the kinematic distance for G21.5–0.9 to ∼4.8 kpc. For Kes 69, the highest velocity of absorption is ∼86 km s−1 and a prominent H i emission feature at ∼112 km s−1 has no respective absorption. These new results suggest that Kes 69 is associated with a newly detected extended 1720-MHz OH maser at velocity of ∼85 km s−1 that originates from within the bright southern radio shell of Kes 69. For G21.5–0.9, the highest velocity of absorption is ∼67 km s−1. The H i absorption spectra of the nearby bright source PMN J1832−1035 and Kes 69 show a common absorption feature at velocity of ∼69 km s−1, which is not seen for G21.5–0.9. The resulting velocity of ∼68 km s−1 gives the best distance estimate of ∼4.8 kpc for G21.5–0.9 and associated young pulsar J1833−1034.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".