Stellar chromospheric activities revealed from the LAMOST-K2 time-domain survey

Henggeng Han, Song Wang, Yu Bai +3

By using the LAMOST time-domain survey data, we study stellar activities based on the ${\mathrm{H}}_{\alpha }$ lines for about 2000 stars in four $K$2 plates. Two indices, $R_{\mathrm{H}\alpha }^{{}^{\prime }}$ and…