Tag: cepheids

The binary fraction in Cepheids revealed by X-ray observations. The paper: “X-Rays in Cepheids: Identifying Low-mass Companions of Intermediate-mass Stars” of N. R. Evans (SAO) recently appeared on ApJ

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Cepheids are important stars for the well-known relation between the period of their pulsations and their intrinsic luminosities. These stars are in fact characterized by regular pulsations whose period increases linearly with their absolute magnitude. Cepheids have a mass of about 5 solar masses, thus their progenitors are B stars in Main Sequence. However, their evolutionary path can be affected

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Cepheids and X-ray emission. The study “X-rays in Cepheids: XMM-Newton Observations of η Aql” of N. R. Evans (SAO-CfA) recently appeared on AJ

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Cepheids are stars of great importance, since they allow to determine the distance of galaxies within a few hundreds of million of light years from us. This is due to the pulsations that characterize these giant stars, which are going through an instable phase of their evolution. Because of these pulsations, the luminosity of these stars varies with a period

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A hidden companion for the cepheid V473 Lyr. The study “X-Ray Observations of the Peculiar Cepheid V473 Lyr Identify A Low-mass Companion” of N. R. Evans (Smithsonian Astrophysical Observatory) recently appeared on AJ AJ

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Cepheids are pulsating giant stars, whose luminosity varies periodically. This is an important class of stars for several reasons. For instance, the period of their pulsations is related to their intrinsic luminosity. This makes cepheids a class of astronomical “standard candles”, e.g. sources whose intrinsic luminosity can be estimated, allowing us to estimate their distances by comparing intrinsic and observed

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