Light and Velocity Variability of Post-AGB Stars
نویسندگان
چکیده
منابع مشابه
Post-AGB stars as testbeds of nucleosynthesis in AGB stars
We construct a data base of 125 post-AGB objects (including R CrB and extreme helium stars) with published photospheric parameters (effective temperature and gravity) and chemical composition. We estimate the masses of the postAGB stars by comparing their position in the (log Teff , log g) plane with theoretical evolutionary tracks of different masses. We construct various diagrams, with the ai...
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In the course of the MUCHFUSS project we recently discovered four radial velocity (RV) variable, hot (Teff ≈ 80 000−110 000 K) post-asymptotic giant branch (AGB) stars. Among them, we found the first known RV variable O(He) star, the only second known RV variable PG 1159 close binary candidate, as well as the first two naked (i.e., without planetary nebula (PN)) H-rich post-AGB stars of spectra...
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In this article we report further investigations of the IRAS selected sample of Planetary Nebula (PN) candidates that was presented in Van de Steene & Pottasch (1993). About 20% of the candidates in that sample have been detected in the radio and/or Hα and later confirmed as PNe. Here we investigate the infrared properties of the IRAS sources not confirmed as PNe. We observed 28 objects in the ...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 2000
ISSN: 0074-1809
DOI: 10.1017/s0074180900002527