New Oe stars in LAMOST DR5

Abstract

Stars of spectral type Oe are very rare. To date, only 13 Oe stars have been identified within our Galaxy. In this paper, we present six new Oe stars and four new B0e stars found in LAMOST DR5. Repeated spectral observations of the same Oe stars show some emission line variability. The H$\beta$ emission of TYC 4801-17-1 shows rapid V/R variation. Phase lags in the V/R ratio of TYC 4801-17-1 spectra are also seen. We found the unusual O4.5 star RL 128 is an Oe star with variable H$\alpha$ intensity and its Ca II triplet emission appears when H$\alpha$ emission reaches maximum intensity. These newly identified early type Oe and B0e stars significantly increase the known sample.

arXiv comment12 pages, 6 figures and 3 tables

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Cited by in corpus (11)

• Overview of the LAMOST survey in the first decade
• Hot stars observed by XMM-Newton II. A survey of Oe and Be stars
• The Single Star Path to Be Stars
• Ultraviolet Spectropolarimetry: on the origin of rapidly rotating B stars
• Identification of new Classical Ae stars in the Galaxy using LAMOST DR5
• Discovery of 2716 hot emission-line stars from LAMOST DR5
• Galactic O-type stars in LAMOST data
• An extensive spectroscopic time series of three Wolf-Rayet stars -- II. A search for wind asymmetries in the dust-forming WC7 binary WR137
• LAMOST J040643.69+542347.8: the fastest Rotator in the Galaxy
• Searching for shell stars in LAMOST DR4 by probing the Fe 42 multiplet lines
• Irregular emission cycles in the Oe star HD 60848