Properties of Oh/ir Stars with the Iras Lrs Spectra
نویسنده
چکیده
1607 OH/IR stars associated with IRAS sources are assembled and the IRAS LRS spectra of 980 OH/IR stars are examined in this paper. The nature of the circumstellar dust for these sources is classiied. The distributions of these subgroups of OH/IR stars in the IRAS color{color diagram and the period{color diagram are interpreted with their evolutionary status. The Galactic and the velocity distributions of these subgroups of OH/IR stars are also presented. The correlations among the expanding velocities of the envelopes, colors, periods and the pumping eeciencies for subgroups of OH/IR stars are investigated to outline the evolutionary status of OH/IR stars.
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