| Name: | Edwin Das |
| Affiliation: | CHRIST (Deemed to be University), Bengaluru |
| Conference ID : | ASI2024_760 |
| Title : | Identification of a new sample of 25000 late-type emission-line stars from LAMOST DR6 |
| Authors : | Edwin Das 1, Blesson Mathew 1, Shridharan B 1, Nidhi Sabu 1, Suman Bhatacharya 1, Vineeth V 1, Robin T, Sreeja S Kartha 1 |
| Authors Affiliation: | 1. CHRIST University, Bangalore, India |
| Mode of Presentation: | Poster |
| Abstract Category : | Stars, Interstellar Medium, and Astrochemistry in Milky Way |
| 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 42023 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 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 valuable addition to the database of emission-line stars. We employed photometric techniques to separate young stars from our sample which shows infrared excess. 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 was classified as F-M-type emission-line stars. Furthermore, stars were grouped, and their properties were studied based on the presence of the activity indicator emission lines. Through this work, a homogeneous sample of late-type emission-line stars was added, which will boost further studies on these sources. |
