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arXiv · 1711.08675

Stellar parameters and H$α$ line profile variability of Be stars in the BeSOS survey

C. Arcos·S. Kanaan·J. Chávez·L. Vanzi·I. Araya·M. Curé
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Abstract

The Be phenomenon is present in about 20$\%$ of the B-type stars. Be stars show variability on a broad range of timescales, which in most cases is related to the presence of a circumstellar disk of variable size and structure. For this reason a time resolved survey is highly desirable in order to understand the mechanisms of disk formation which are still poorly understood. In addition, a complete observational sample would improve the statistical significance of the study of the stellar and disk parameters. The "Be Stars Observation Survey" (BeSOS) is a survey containing reduced spectra obtained using the echelle spectrograph PUCHEROS with a spectral resolution of 17000 in the range of 4260-7300 $\textÅ$. BeSOS's main objective is to offer consistent spectroscopic and time resolved data obtained with one instrument. The user can download or plot the data and get the stellar parameters directly from the website. We also provide a star-by-star analysis based on photometric, spectroscopic and interferometric data as well as general information about the whole BeSOS sample. Recently, BeSOS led to the discovery of a new Be star HD 42167 and facilitated study of the V/R variation of HD 35165 and HD 120324, the steady disk of HD 110335 and the Be shell status of HD 127972. Optical spectra used in this work, as well as the derived stellar parameters are available online in \url{http://besos.ifa.uv.cl}.

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C. Arcos, S. Kanaan, J. Chávez, L. Vanzi, I. Araya, M. Curé. 2017-11-23. Stellar parameters and H$α$ line profile variability of Be stars in the BeSOS survey. https://doi.org/10.1093/mnras%2Fstx3075

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