The Southern H II Region Discovery Survey. II. The Full Catalog
Bibliographic record
Abstract
Abstract The Southern H ii Region Discovery Survey (SHRDS) is a 900 hr Australia Telescope Compact Array 4–10 GHz radio continuum and radio recombination line (RRL) survey of Galactic H ii regions and infrared-identified H ii region candidates in the southern sky. For this data release, we reprocess all previously published SHRDS data and include an additional ∼450 hr of observations. The search for new H ii regions is now complete over the range 259° < ℓ < 346°, ∣ b ∣ < 4° for H ii region candidates with predicted 6 GHz continuum peak brightnesses ≳30 mJy beam −1 . We detect radio continuum emission toward 730 targets altogether including previously known nebulae and H ii region candidates. By averaging ∼18 RRL transitions, we detect RRL emission toward 206 previously known H ii regions and 436 H ii region candidates. Including the northern sky surveys, over the last decade the H ii Region Discovery Surveys have more than doubled the number of known Galactic H ii regions. The census of H ii regions in the Wide-field Infrared Survey Explorer (WISE) Catalog of Galactic H ii Regions is now complete for nebulae with 9 GHz continuum flux densities ≳250 mJy. We compare the RRL properties of the newly discovered SHRDS nebulae with those of all previously known H ii regions. The median RRL FWHM line width of the entire WISE Catalog H ii region population is 23.9 km s −1 and is consistent between Galactic quadrants. The observed Galactic longitude–velocity asymmetry in the population of H ii regions probably reflects underlying spiral structure in the Milky Way.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.003 | 0.003 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.021 | 0.022 |
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 source (direct Gemma or distilled Codex), 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".