On the Nature of Regular Pulsation in Two LBV Stars of NGC 300

• Autorzy: Dziembowski W. A. , Sławińska J.
• Języki publikacji: EN

Abstrakty

EN

Two A-type supergiants in NGC 300 exhibit periodic light variations. The measured periods are 72.5 and 96.1 days. We show that the variability may be explained by the excitation of strange mode driven by the opacity mechanism acting in the layer of the iron opacity bump. The explanation requires that the two stars are significantly undermassive. In sequences of stellar models with decreasing luminosity-to-mass ratio, the unstable strange modes represent continuations of strictly aperiodic thermal modes.

Słowa kluczowe

EN

stars: oscillations; supergiants; stars: evolution; instabilities

• Wydawca: Copernicus Foundation for Polish Astronomy
• Czasopismo: Acta Astronomica
• Rocznik: 2005
• Tom: Vol. 55, No. 2
• Strony: 195--204
• Opis fizyczny: Bibliogr. 8 poz., tab.

Twórcy

autor

Dziembowski W. A.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
• Copernicus Astronomical Centre, ul. Bartycka 18, 00-716 Warsaw, Poland

autor

Sławińska J.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

Bibliografia

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