Mode switching in the nearby Mira-like variable R Doradus
نویسندگان
چکیده
منابع مشابه
Mode switching in the nearby Mira-like variable R Doradus
We discuss visual observations spanning nearly 70 years of the nearby semiregular variable R Doradus. Using wavelet analysis, we show that the star switches back and forth between two pulsation modes having periods of 332 days and about 175 days, the latter with much smaller amplitude. Comparison with model calculations suggests that the two modes are the first and third radial overtone, with t...
متن کاملThe evolution of the Mira variable R Hydrae
The Mira variable R Hydrae is well known for its declining period, which Wood & Zarro (1981) attributed to a possible recent thermal pulse. Here we investigate the long-term period evolution, covering 340 years, going back to its discovery in AD 1662. The data includes photometric monitoring by amateur and other astronomers over the last century, and recorded dates of maximum for earlier times....
متن کاملThe Infrared Spectrum of R Doradus
Here, we present our modelling (Ryde & Eriksson, 2002) of the 2.6 − 3.7μm spectrum of the red semiregular variable R Doradus observed with the Short-Wavelength Spectrometer on board the Infrared Space Observatory. We will also present the entire spectrum of R Dor up to 5μm based on our model photosphere in order to show which molecules are important for the emergent spectrum. 1. Observations an...
متن کاملSecular Evolution in Mira Variable
Stellar evolution theory predicts that asymptotic giant branch stars undergo a series of short thermal pulses that significantly change their luminosity and mass on timescales of hundreds to thousands of years. These pulses are confirmed observationally by the existence of the short-lived radioisotope technetium in the spectra of some of these stars, but other observational consequences of ther...
متن کاملLINEAR PULSATION CHARACTERISTICS OF MIRA VARIABLE STARS
The linear adiabatic pulsation-periods of Mira variable stars have been derived. Approximately 2701[1]models were calculated for M = 0.7 MΘ to 2 MΘ stars with radii from 180 RΘ to 340 RΘ and luminosities from 2800 LΘ to 10,000 LΘ. The chemical composition of all models is (X,Z) = (0.7,0.02). From the result of this study, linear relations on Luminosity-Period-Mass relationship and luminosity-pe...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 1998
ISSN: 0035-8711,1365-2966
DOI: 10.1046/j.1365-8711.1998.02069.x