Context. Oe stars possibly form an extension to higher temperatures of the Be phenomenon, but it is still unclear whether these stars have disks. Aims. X-ray spectra could provide hints for interactions of the star with a putative surrounding disk. Methods. We obtained XMM-Newton observations of two Oe stars, HD 45314 and HD 60848. Spectra and light curves were extracted and analysed. Optical spectra were also obtained to support the X-ray observations. Results. We find that both stars display very different X-ray properties. Whilst HD 60848 has an X-ray spectrum and emission level typical for its spectral type, HD 45314 displays a very hard X-ray emission, dominated by a thermal plasma with kT ∼ 21 keV. Furthermore, HD 45314 displays count rate variations by a factor 2 on timescales of ∼ 103 s and a high log (LX/L bol) =-6.10 ± 0.03. Conclusions. The X-ray properties of HD 45314 indicate that this star is a new member of the class of γ Cas analogs, the first one among the original category of Oe stars.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science