Properties of galactic B[e] supergiants: IV. Hen 3-298 and Hen 3-303

Abstract

We present the results of optical and near-IR spectroscopic and near-IR photometric observations of the emission-line stars Hen 3–298 and Hen 3–303. Strong emission in the Hα line is found in both objects. The presence of Fe II and [O I] emission lines in the spectrum of Hen 3–298 indicates that it is a B[e] star. The double-peaked CO line profiles, found in the infrared spectrum of Hen 3–298, along with the optical line profiles suggest that the star is surrounded by a rotating circumstellar disc. 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 5.1 and a spectral type of no earlier than B3 for Hen 3–298. Hen 3–303 seems to be a less luminous B-type object ( 4.3), located in the same spiral arm.