Long Secondary Periods in variable red giants
نویسندگان
چکیده
منابع مشابه
Long Secondary Periods in Variable Red Giants
We present a study of a sample of LMC red giants exhibiting Long Secondary Periods (LSPs). We use radial velocities obtained from VLT spectral observations and MACHO and OGLE light curves to examine properties of the stars and to evaluate models for the cause of LSPs. This sample is much larger than the combined previous studies of Hinkle et al. (2002) and Wood, Olivier & Kawaler (2004). Binary...
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Observational arguments supporting the binary explanation of the long secondary periods (LSP) phenomenon in red giants are presented. Photometry of about 1200 semiregular variables with the LSP in the Large Magellanic Cloud are analyzed using the MACHO and OGLE photometry. For about 5% of these objects additional ellipsoidal-like or eclipsing-like modulation with the same periods as the LSP is ...
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Infrared J and K photometry has been obtained of all red giants in the half square degree region of the LMC bar searched for variables using the MACHO database by Wood et al. (1999). The K–logP diagram shows the five distinct period–luminosity sequences which are also evident in the MACHO photometry. The K–logP plot allows identification of the Mira sequence from among the five observed sequenc...
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We study the brightness variations of galactic red supergiant stars using long-term visual light curves collected by the American Association of Variable Star Observers (AAVSO) over the last century. The full sample contains 48 red semiregular or irregular variable stars, with a mean time-span of observations of 61 years. We determine periods and period variability from analyses of power densit...
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We present a period-luminosity-amplitude analysis of 5899 red giant and binary stars in the Large Magellanic Cloud, using publicly available observations of the MACHO project. For each star, we determined new periods, which were double-checked in order to exclude aliases and false periods. The period-luminosity relations confirm the existence of a short-period, small-amplitude P–L sequence at p...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2009
ISSN: 0035-8711,1365-2966
DOI: 10.1111/j.1365-2966.2009.15401.x