Abstract
Four different models for a K-giant atmosphere (T e=4500K, logg=2) have been computed. Each model is characterized by the inclusion of different opacity sources (H, H−, σ(H), metals, blanketing effect, He−) in order to obtain an evaluation of the model sensitivity concerning the atmospheric structure and the emergent flux. The results show that hydrogen, metals and blanketing effect must be taken into account to achieve self-consistent and reliable models.
A picture of the influence of the frequency distribution of the absorption coefficient on the model features is also shown.
Sommario
Sono stati calcolati quattro differenti modelli di una stella gigante K(T e=4500K, logg=2). Ogni modello è caratterizzato dalla inclusione di differenti sorgenti di opacità (H, H−, σ (H), metalli, effetto ‘blanketing’, He−) per ottenere una valutazione della sensibilità del modello per quel che riguarda la struttura atmosferica ed il flusso emergente. I risultati ottenuti mostrano che per costruire modelli auto-consistenti e con un buon grado di affidabilità occorre tener conto almeno delle seguenti sorgenti di opacità: H, metalli, effetto ‘blanketing’.
Si mostra inoltre come sia possibile una descrizione schematica dell'influenza del coefficiente di assorbimento sulle varie caratteristiche del modello.
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Natta, A., Preite-Martinez, A. Stellar atmospheres models of K-giant stars: the influence of opacity sources. Astrophys Space Sci 9, 440–452 (1970). https://doi.org/10.1007/BF00649582
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DOI: https://doi.org/10.1007/BF00649582