Survey of \(\hbox {H}{\varvec{\alpha }}\) emission-line stars in the star-forming region IC 5070

Abstract

Actively accreting young stellar objects show H\(\alpha \) emission line in their spectra. We present the results of survey for H\(\alpha \) emission-line stars in the star-forming region IC 5070 taken with 2-m Himalyan Chandra Telescope. Based on the H\(\alpha \) slitless spectroscopy data, we identified 131 emission-line stars in \(\sim \)0.29 square degrees area of the IC 5070 region. Using Gaia early data release 3, we estimated the mean proper motion and parallax of the emission-line stars. We also estimated the mean distance and reddening toward the region using the emission-line stars, which are \(\sim \)833 pc and \(\sim \)2 mag, respectively. By examining the locations of these stars in the color–magnitude diagrams constructed using Gaia and PanSTARRS1 data, we found that a majority of the H\(\alpha \) emitters are young low-mass (\({<}1.5\, M_\odot \)) stars. We also compared our catalog of emission-line stars with the available young stellar catalogs and found that most of them are class ii/flat spectrum sources with the spectral type ranging from K to M. Based on the proper motion/parallax values and locations on the color–magnitude diagrams, about 20 emission-line stars are flagged as non-members. The relative proper motion of the emission-line stars with respect to the ionizing source suggest the possibility of the ‘rocket effect’ scenario in the remnant cloud (BRC 31).