Name: Edwin Das
Affiliation: CHRIST Deemed to be University, Bangaluru
Conference ID : ASI2022_83
Title : Identification of a new sample of 25000 late-type emission-line stars from LAMOST DR6
Authors : Edwin Das, B Shridharan, Blesson Mathew, V Vineeth
Abstract Type: Poster*
Abstract Category : Stars, ISM and Galaxy
Abstract : The study of emission-line stars is emerging as an active field of research, particularly for science related to disc dynamics and stellar evolution. Shridharan et al. (2021) cataloged a sample of 3339 OBA emission-line stars in the Galaxy using the spectra from LAMOST DR5, among which 2716 were new detections. We adopted the same methodology and quality cut (e.g. SNR > 10; removing bad quality flags) to identify a sample of 39820 late-type emission-line stars from LAMOST Data Release 6. These stars were preferentially selected, in-tune with the `late-type' definition, to be in the spectral range from F5 to M9. We developed a python routine for detecting the emission-line stars, which is quantified by means of an emission peak around the Hα line. Interestingly, about 25000 stars do not have any records in SIMBAD and hence will be a value addition to the database of emission-line stars. The giant candidates were separated from the rest using the surface gravity values and through the evaluation of the spectral indices of CaH and TiO molecular bands. The rest of the sample of emission-line stars were classified into Classical T Tauri stars and dwarfs, based on their optical and infrared properties.