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Record W1662364370

The gamma Velorum binary system

2000· article· en· W1662364370 on OpenAlexaff
Orsola De Marco, W. Schmütz, P. A. Crowther, D. J. Hillier, Luc Dessart, A. de Koter, J. Schweickhardt

Bibliographic record

VenueUvA-DARE (University of Amsterdam) · 2000
Typearticle
Languageen
FieldMaterials Science
TopicNuclear Materials and Properties
Canadian institutionsUniversité Laval
FundersNederlandse Organisatie voor Wetenschappelijk OnderzoekDeutsche ForschungsgemeinschaftNational Aeronautics and Space Administration
KeywordsPhysicsAstrophysicsBinary numberBinary starAstronomyStars
DOInot available

Abstract

fetched live from OpenAlex

In this paper we derive stellar parameters for the Wolf-Rayet star in the γ Velorum binary system (WR11), from a detailed non-LTE model of its optical and infrared spectra.Compared to the study of Schaerer et al., the parameters of the WC8 star are revised to a hotter effective temperature (T eff ∼ 57 kK), a higher luminosity (log(L/L ) = 5.00), and a lower mass-loss rate (log( Ṁ / M /yr) = -5.0,using a 10% clumping filling factor).These changes lead to a significant decrease in wind efficiency number, from 144 to 7, so that the driving mechanism of the wind of this WR star may be simply radiation pressure on lines.The derived spectroscopic luminosity is found to be 40% lower than that derived by De Marco & Schmutz through the mass-luminosity relationship for WR stars (log(L/L ) = 5.2).The paper furthermore presents a comparison of the independently-developed modelling programs, cmfgen and isa-wind.Overall, there seems to be very reasonable agreement between the derived parameters for WR11, except for the carbon content, which is 2 times higher for cmfgen (C/He=0.15 vs. 0.06, by number).The comparison also confirms a disparity in the predicted flux at λ<400 Å, found by Crowther et al., which will have effects on several nebular line strengths.The paper also presents the first independent check of the photon loss mechanism proposed by Schmutz.We conclude that, not only is it important to include very many lines to realistically model line blanketing, but in particular those ones that critically interact with strong resonance lines (e.g.He ii λ303.78).The inclusion of these latter lines may significantly alter the wind ionization structure.Based on observations collected at the European Southern Observatory at La Silla, Chile.ESO proposals Nrs.56.D-327, 57.D-517 and 56.

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: none
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.009
Threshold uncertainty score0.032

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0010.000
Bibliometrics0.0010.000
Science and technology studies0.0010.000
Scholarly communication0.0010.000
Open science0.0000.001
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0090.001

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.

Opus teacher head0.008
GPT teacher head0.162
Teacher spread0.154 · 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

Citations1
Published2000
Admission routes1
Has abstractno

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