A K-band spectral mini-survey of Galactic B[e] stars

LIERMANN, A.; SCHNURR, O.; KRAUS, M.; KREPLIN, A.; ARIAS, M. L.; CIDALE, L.

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2014 vol. 443 p. 947 - 956

0035-8711

We present a mini-survey of Galactic B[e] stars mainly under taken with the Large Binocular Telescope (LBT). B[e] stars show morphologicalfeatureswith hydrogenemission lines and and infrared excess, attributed to warm circumstellar dust. In general, these features are  assumed to arise from dense, non-spherical, disk-forming circumstellar material in which molecules and dust can condensate. Due to the lack of reliable luminosities, the class of Galactic B[e] stars contains stars at very different stellar evolutionary phases like Herbig AeBe, supergiants or planetary nebulae. We took near-infrared long-slit K-band spectra for a sample of Galactic B[e] stars with the LBT-LuciI. Prominent spectral features, such as the Brackett γline and CO band heads are objects. Among others we find one LBV candidate (MWC314), one supergiant B[e] candidate with 13CO (MWC137) and in two cases (MWC623 and AS381) indications for the existence of a late-type binary companion, complementary to previous studies. For MWC84, IR spectra were taken at different epochs with LBT LuciI and the GNIRS spectrograph at the Gemini North telescope. The new data show the disappearance of the circumstellar CO emission around this star, previously detectable over decades. Also no signs of a recent prominent eruption leading to the formation of new CO disk emission are found during 2010 and 2013.