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Properties of galactic B[e] supergiants. IV. Hen3-298 and Hen3-303

A. S. Miroshnichenko·K. S. Bjorkman·M. Grosso·K. Hinkle·H. Levato·F. Marang
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Abstract

We present the results of optical and near-IR spectroscopic and near-IR photometric observations of the emission-line stars Hen3-298 and Hen3-303. Strong emission in the H-alpha line is found in both objects. The presence of Fe II and [O I] emission lines in the spectrum of Hen3-298 indicates that it is a B[e] star. The double-peaked CO line profiles, found in the infrared spectrum of Hen3-298, along with the optical line profiles suggest that the star is surrounded by a rotating circumstellar disk. Both objects also show infrared excesses, similar to those of B[e] stars. The radial velocities of the absorption and emission lines as well as a high reddening level suggest that the objects are located in the Norma spiral arm at a distance of 3-4.5 kpc. We estimated a luminosity of log (L/L_sun) ~ 5.1 and a spectral type of no earlier than B3 for Hen3-298. Hen3-303 seems to be a less luminous B-type object (log (L/L_sun) ~ 4.3), located in the same spiral arm.

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A. S. Miroshnichenko, K. S. Bjorkman, M. Grosso, K. Hinkle, H. Levato, F. Marang. 2005-03-07. Properties of galactic B[e] supergiants. IV. Hen3-298 and Hen3-303. https://doi.org/10.1051/0004-6361%3A20052726

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