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تسجيل مستخدم جديدDetection of Flare-associated CME Candidates on Two M-dwarfs by GWAC and Fast, Time-resolved Spectroscopic Follow-ups
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The flare-associated stellar coronal mass ejection (CME) in solar-like and late type stars is quite essential for the habitability of an exoplanet. In this paper, we report detection of flare-associated CMEs in two M-dwarfs, thanks to the high cadence survey carried out by the Ground Wide-angle Camera system and the fast photometric and spectroscopic follow-ups. The flare energy in $R-$band is determined to be $1.6times10^{35} mathrm{erg}$ and $8.1times10^{33} mathrm{erg}$ based on the modeling of their light curves. The time-resolved spectroscopyic observations start at about 20 and 40 minutes after the trigger in both cases. The large projected maximum velocity of $sim500-700 mathrm{km s^{-1}}$ suggests that the high velocity wing of their H$alpha$ emission lines are most likely resulted from a CME event in both stars, after excluding the possibility of chromospheric evaporation and coronal rain. The masses of the CMEs are estimated to be $1.5-4.5times10^{19} mathrm{g}$ and $7.1times10^{18} mathrm{g}$.
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