The quasar 0805+046 as a helium-rich shell star
نویسندگان
چکیده
منابع مشابه
Strong period decrease in the Mira star S Sex: a possible helium-shell flash
Analysis of visual observations of the Mira-type variable star S Sex showed that the period of pulsation has decreased strongly since 1984 from 264.8 days to 249.4 days. The cycle length variations were tested by the method of contingency tables and by the span test, so that random or accumulative errors in the period variation were excluded. Our results are in good agreement with the theoretic...
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ژورنال
عنوان ژورنال: Astrophysics and Space Science
سال: 1985
ISSN: 0004-640X,1572-946X
DOI: 10.1007/bf00650159