MétaCan
Menu
← Back to cohort
Record W2896420003 · doi:10.3847/1538-4357/aadf88

Broad Wings around Hα and Hβ in the Two S-type Symbiotic Stars Z Andromedae and AG Draconis

2018· article· en· W2896420003 on OpenAlexaboutno aff

Bibliographic record

VenueThe Astrophysical Journal · 2018
Typearticle
Languageen
FieldPhysics and Astronomy
TopicStellar, planetary, and galactic studies
Canadian institutionsnot available
Fundersnot available
KeywordsBalmer seriesStarsThomson scatteringElectron densitySpectral lineScatteringEmission spectrumElectron temperatureRaman scatteringDoppler effect

Abstract

fetched live from OpenAlex

Abstract Symbiotic stars often exhibit broad wings around Balmer emission lines, whose origin is still controversial. We present high-resolution spectra of the S type symbiotic stars Z Andromedae and AG Draconis obtained with the ESPaDOnS and the 3.6 m Canada–France–Hawaii Telescope to investigate the broad wings around Hα and Hβ. When Hα and Hβ lines are overplotted in the Doppler space, it is noted that Hα profiles are overall broader than Hβ in these two objects. Adopting a Monte Carlo approach, we consider the formation of broad wings of Hα and Hβ through Raman scattering of far-UV radiation around Lyβ and Lyγ and Thomson scattering by free electrons. Raman scattering wings are simulated by choosing an H i region with a neutral hydrogen column density N H i and a covering factor CF. For Thomson wings, the ionized scattering region is assumed to fully cover the Balmer emission nebula and is characterized by the electron temperature T e and the electron column density N e. Thomson wings of Hα and Hβ have the same width that is proportional to . However, Raman wings of Hα are overall three times wider than Hβ counterparts, which is attributed to different cross sections for Lyβ and Lyγ. Normalized to have the same peak values and presented in the Doppler factor space, Hα wings of Z And and AG Dra are observed to be significantly wider than their Hβ counterparts, favoring the Raman scattering origin for broad Balmer wings.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not 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.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.002
Threshold uncertainty score0.004

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.000
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0000.000

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.

Opus teacher head0.011
GPT teacher head0.240
Teacher spread0.229 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designObservational
Domainnot available
GenreEmpirical

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".

Quick stats

Citations7
Published2018
Admission routes1
Has abstractyes

Explore more

Same venueThe Astrophysical Journal→Same topicStellar, planetary, and galactic studies→French-language works237,207→