Magakian T.Yu.
Byurakan astrophysical oservatory, Armenia
We present some results of the recently (in 2020) started project of the long-slit spectroscopy of the deeply embedded in the dark clouds objects, which were found during the searches of new HH flows near the infrared sources (IRS). In the course of these searches we found that many of abovementioned IRS not only generate the HH flows but actually also are visible in the optical range. This project was initiated to better understand their nature and evolutional stage.
Among the examples presented are the “fossil” FUor RNO 54, the presumable FU Ori-like star V565 Mon and several previously unstudied objects in Mon R1 and Mon R2 associations. They include IRAS 06297+1021 W (very probable new FU Ori-like object), 2MASS 06084223-0657385 (unusual object with extended envelope), V963 Mon (probable EXor, an analogue of PV Cep?), CPM 19 (a famous IR source, quite peculiar variable object) and other stars.
This initial long-slit spectral study of the IR young stars in dark clouds, including the deeply embedded Class I sources, allowed to make some preliminary conclusions. The studied objects can be roughly divided in three groups: 1. Objects with continual and featureless spectrum, with narrow Ha emission; 2. Stars, which besides of strong Ha emission, have prominent shock-excited emission lines; 3. Stars with developed not typical for T Tauri type emission-line spectrum, as well as new FUor-like objects.