A Pre‐Protostellar Core in L1551. II. State of Dynamical and Chemical Evolution
Bibliographic record
Abstract
Both analytic and numerical radiative transfer models applied to high spectral resolution CS and N 2 H + data give insight into the evolutionary state of L1551 MC. This recently discovered pre-protostellar core in L1551 appears to be in the early stages of dynamical evolution. Line-of-sight infall velocities of ≳0.1 km s -1 are needed in the outer regions of L1551 MC to adequately fit the data. This translates to an accretion rate of ~10 -6 M ☉ yr -1 , uncertain to within a factor of 5 owing to unknown geometry. The observed dynamics are not due to spherically symmetric gravitational collapse and are not consistent with the standard model of low-mass star formation. The widespread, fairly uniform CS line asymmetries are more consistent with planar infall. There is modest evidence for chemical depletion in the radial profiles of CS and C 18 O, suggesting that L1551 MC is also chemically young. The models are not very sensitive to chemical evolution. L1551 MC lies within a quiescent region of L1551 and is evidence for continued star formation in this evolved cloud.
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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) | 0.001 | 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".