Detection of Flare-associated CME Candidates on Two M-dwarfs by GWAC and Fast, Time-resolved Spectroscopic Follow-ups

Abstract

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 $1.6\times 10^{35}\mathrm{erg}$ and $8.1\times 10^{33}\mathrm{erg}$ 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 $\sim 500-700\mathrm{km}{\mathrm{s}}^{-1}$ 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 $1.5-4.5\times 10^{19}\mathrm{g}$ and $7.1\times 10^{18}\mathrm{g}$.

arXiv comment15 pages, 10 figures and 5 tables, accepted by ApJ

References in corpus (43)

• Gaia Data Release 2. Summary of the contents and survey properties
• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• Intrinsic Colors, Temperatures, and Bolometric Corrections of Pre-Main Sequence Stars
• The Revised TESS Input Catalog and Candidate Target List
• The stellar activity-rotation relationship and the evolution of stellar dynamos
• Painting a portrait of the Galactic disc with its stellar clusters
• Global Energetics of Thirty-Eight Large Solar Eruptive Events
• Kepler Flares II: The Temporal Morphology of White-Light Flares on GJ 1243
• Time-Resolved Properties and Global Trends in dMe Flares from Simultaneous Photometry and Spectra
• Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18
• Sun-as-a-star Observation of White-Light Flares
• The Xinglong 2.16-m Telescope: Current Instruments and Scientific Projects
• From Radio to X-ray: Flares on the dMe Flare Star EV Lacertae
• Line temperatures and elemental abundances in HII galaxies
• The Stellar CME-flare relation: What do historic observations reveal?
• Magnetic reconnection between a solar filament and nearby coronal loops
• Strong dipole magnetic fields in fast rotating fully convective stars
• A stellar flare-coronal mass ejection event revealed by X-ray plasma motions
• The quest for stellar coronal mass ejections in late-type stars: I. Investigating Balmer-line asymmetries of single stars in Virtual Observatory data
• Solar Flares and Coronal Mass Ejections: A Statistically Determined Flare Flux-CME Mass Correlation
• Scaling K2. I. Revised Parameters for 222,088 K2 Stars and a K2 Planet Radius Valley at 1.9 $R_{\oplus }$
• MOST Observations of our Nearest Neighbor: Flares on Proxima Centauri
• Stellar flares observed in long cadence data from the Kepler mission
• K2 Ultracool Dwarfs Survey. III. White Light Flares are Ubiquitous in M6-L0 Dwarfs
• A search for flares and mass ejections on young late-type stars in the open cluster Blanco-1
• Spatial Relationship between Solar Flares and Coronal Mass Ejections
• The effect of magnetic activity saturation in chromospheric flux-flux relationships
• On-disk coronal rain
• Flares in Open Clusters with K2. I. M45 (Pleiades), M44 (Praesepe) and M67
• A Multi-Wavelength Perspective of Flares on HR 1099: Four Years of Coordinated Campaigns
• The largest M dwarfs flares from ASAS-SN
• The Influence of Coronal Mass Ejections on the Mass-loss Rates of Hot-Jupiters
• A Monster CME Obscuring A Demon Star Flare
• Search for flares and associated CMEs on late-type main-sequence stars in optical SDSS spectra
• Astrometric and photometric initial mass functions from the UKIDSS Galactic Clusters Survey: III Praesepe
• Different Signatures of Chromospheric Evaporation in Two Solar Flares Observed with IRIS
• Stellar coronal mass ejections II. Constraints from spectroscopic observations
• Peculiar Stationary EUV Wave Fronts in the eruption on 2011 May 11
• An explanation of remarkable emission line profiles in post-flare coronal rain
• X-ray Flares of EV Lac: Statistics, Spectra, Diagnostics
• A Real-time Automatic Validation System for Optical Transients detected by GWAC
• A Study on Red Asymmetry of H-alpha Flare Ribbons Using Narrowband Filtergram in the 2001 April 10 Solar Flare
• A $\Delta R\sim 9.5$ mag Super Flare of An Ultracool Star Detected by $\text{SVOM/GWAC}$ System

Cited by in corpus (13)

• Detection of Flare-induced Plasma Flows in the Corona of EV Lac with X-ray Spectroscopy
• Possible detection of coronal mass ejections on late-type main-sequence stars in LAMOST medium-resolution spectra
• Stellar Coronal Mass Ejections
• Red Asymmetry of H${}_{\alpha }$ Line Profiles during the flares on the active RS CVn-type star II Pegasi
• Flaring-associated Complex Dynamics in Two M-dwarfs Revealed by Fast, Time-resolved Spectroscopy
• O'TRAIN: a robust and flexible Real/Bogus classifier for the study of the optical transient sky
• Photometric observations of flares on AD Leo from GWAC-F30 and TESS
• Magnetic activities and parameters of 43 flare stars in the GWAC archive
• The Evryscope Fast Transient Engine: Real-Time Detection for Rapidly Evolving Transients
• The white-light superflares from cool stars in GWAC triggers
• Convolutional Neural Networks for Searching Superflares from Pixel-level Data of the Transiting Exoplanet Survey Satellite
• A huge-amplitude white-light superflare on a L0 brown dwarf discovered by GWAC survey
• Doppler-shifted Signatures in the Chromospheric Line Profiles of II Pegasi