Observations of H α , iron , and oxygen lines in B , Be , and shell stars

نویسنده

  • M. I. Nouh
چکیده

Observations of B, Be, and shell stars in different spectral regions are important for putting constraints on modeling these stars. Echelle spectrographs as well as the high sensitivity of modern detectors in the red part of the spectrum provide a wealth of the information contained in the whole visible and near infrared regions obtained simultaneously. The aim of this paper is a spectroscopic survey of line profiles of Hα and selected non-hydrogenic lines of iron and oxygen in the visual and near infrared region for selected bright B and Be stars. We mainly use the echelle observations secured using the HEROS (Heidelberg Extended Range Optical Spectrograph) spectrograph attached to the Ondřejov 2m telescope supplemented by several CCD coudé spectra.

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تاریخ انتشار 2005