Interstellar OH<sup>+</sup>, H<sub>2</sub>O<sup>+</sup>and H<sub>3</sub>O<sup>+</sup>along the sight-line to G10.6–0.4
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
We report the detection of absorption lines by the reactive ions OH<sup>+<sup/>, H<sub>2<sub/>O<sup>+<sup/>and H<sub>3<sub/>O<sup>+<sup/> along the line of sight to the submillimeter continuum source G10.6–0.4 (W31C). We used the <i>Herschel<i/> HIFI instrument in dual beam switch mode to observe the ground state rotational transitions of OH<sup>+<sup/> at 971 GHz, H<sub>2<sub/>O<sup>+<sup/> at 1115 and 607 GHz, and H<sub>3<sub/>O<sup>+<sup/> at 984 GHz. The resultant spectra show deep absorption over a broad velocity range that originates in the interstellar matter along the line of sight to G10.6–0.4 as well as in the molecular gas directly associated with that source. The OH<sup>+<sup/> spectrum reaches saturation over most velocities corresponding to the foreground gas, while the opacity of the H<sub>2<sub/>O<sup>+<sup/> lines remains lower than 1 in the same velocity range, and the H<sub>3<sub/>O<sup>+<sup/>line shows only weak absorption. For LSR velocities between 7 and 50 km s<sup>-1<sup/> we estimate total column densities of <i>N<i/>(OH<sup>+<sup/>) <i>≥<i/> 2.5 × 10<sup>14<sup/> cm<sup>-2<sup/>, <i>N<i/>(H<sub>2<sub/>O<sup>+<sup/>) ~6 × 10<sup>13<sup/> cm<sup>-2<sup/> and <i>N<i/>(H<sub>3<sub/>O<sup>+<sup/>) ~4.0 × 10<sup>13<sup/> cm<sup>-2<sup/>. These detections confirm the role of O<sup>+<sup/> and OH<sup>+<sup/> in initiating the oxygen chemistry in diffuse molecular gas and strengthen our understanding of the gas phase production of water. The high ratio of the OH<sup>+<sup/> by the H<sub>2<sub/>O<sup>+<sup/> column density implies that these species predominantly trace low-density gas with a small fraction of hydrogen in molecular form.
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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) | 0.002 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.002 |
| 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 it