Distance to the SNR CTB109/AXP 1E 2259+586 by H<scp>i</scp>absorption and self-absorption
Bibliographic record
Abstract
Abstract We suggest a revised distance to the supernova remnant G109.1−1.0 (CTB109) and its associated anomalous X-ray pulsar (AXP)1E2259+586 by analysing 21-cm Hi-line and 12CO-line spectra of CTB109, Hii region Sh152 and the adjacent molecular cloud complex. CTB109 has been established to be interacting with a large molecular cloud (recession velocity at v=−55kms−1). The highest radial velocities of absorption features towards CTB109 (−56kms−1) and Sh152 (−65kms−1) are larger than the recombination line velocity (−50kms−1) of Sh152 demonstrating the velocity reversal within the Perseus Arm. The molecular cloud has cold Hi column density large enough to produce Hi self-absorption (HISA) and Hi narrow self-absorption (HINSA) if it was at the near side of the velocity reversal. Absence of both HISA and HINSA indicates that the cloud is at the far side of the velocity reversal within the Perseus Arm, so we obtain a distance for CTB109 of 4 ± 0.8kpc. The new distance still leads to a normal explosion energy for CTB 109/AXP 1E 2259+586.
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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 | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.005 | 0.001 |
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".