ON THE DYNAMICAL EVOLUTION OF H II REGIONS: AN INVESTIGATION OF THE IONIZED COMPONENT OF W4, A GALACTIC CHIMNEY CANDIDATE. II. KINEMATICS AND DYNAMICS IN THE LATITUDE RANGE 3° <<i>b</i>⩽ 7°
Bibliographic record
Abstract
In the second of this two-paper series, we present results associated with an Hα investigation, obtained using the Fabry–Perot interferometer FaNTOmM, of the tenuous ionized material found embedded in the northern portion of W4. W4 is a promising candidate for a galactic chimney, likely connected with the galactic corona, and presents evidence of shell fragmentation. We present the quantitative method for identifying shell breakout that allows us to characterize the giant H i supershell/H ii region W4 as enclosing a galactic chimney in formation. On a range of approximately 125 pc, two "south-to-north" radial velocity gradients are detected, ∇ v = (−)0.17 km s −1 pc −1 (3 5 ⩽ b < 6 3) and ∇ v = (−)3.13 km s −1 pc −1 (6 3 ⩽ b ⩽ 6 5). This leads to radial velocities, slightly above the vicinity of the shell's polar cap, of −70 km s −1 , blueshifted by nearly 25 km s −1 with respect to the H i supershell. The kinematic behavior is in agreement with a rarefaction scenario if the W4 superbubble presents a tilt toward the observer. This angle of inclination is estimated between 9° and 27° with respect to the plane of the sky. A line-narrowing gradient is correlated with the radial velocity gradient. The large-scale trends in radial velocities and line widths correspond to highly accelerated, well-parallelized outflows of vented ionized material. This kinematic signature is expected from the chimney model. The dynamical age of the W4 chimney is estimated at 4.1 Myr and constraints shell instabilities to have developed at latitudes lower than the blowout threshold height. Our work contributes to the evidence that the star cluster IC 1805 partially sustains the low-galactic corona above the Perseus arm.
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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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 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".