Investigating magnetic activity in very stable stellar magnetic fields: long-term photometric and spectroscopic study of the fully convective M4 dwarf V374 Peg

@article{Vida2016InvestigatingMA,
  title={Investigating magnetic activity in very stable stellar magnetic fields: long-term photometric and spectroscopic study of the fully convective M4 dwarf V374 Peg},
  author={Kriszti{\'a}n Vida and L. Kriskovics and Katalin Ol'ah and Martin Leitzinger and Petra Odert and Zs. KHov'ari and Heidi Korhonen and Robert Greimel and Russell M. Robb and B. Cs'ak and J. Kov'acs},
  journal={arXiv: Solar and Stellar Astrophysics},
  year={2016}
}
The ultrafast-rotating ($P_\mathrm{rot}\approx0.44 d$) fully convective single M4 dwarf V374 Peg is a well-known laboratory for studying intense stellar activity in a stable magnetic topology. As an observable proxy for the stellar magnetic field, we study the stability of the light curve, and thus the spot configuration. We also measure the occurrence rate of flares and coronal mass ejections (CMEs). We analyse spectroscopic observations, $BV(RI)_C$ photometry covering 5 years, and additional… 
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References

SHOWING 1-10 OF 58 REFERENCES
The stable magnetic field of the fully convective star V374 Peg
We report in this paper phase-resolved spectropolarimetric observations of the rapidly rotating fully convective M4 dwarf V374 Peg, on which a strong, mainly axisymmetric, large-scale poloidal
DETECTING DIFFERENTIAL ROTATION AND STARSPOT EVOLUTION ON THE M DWARF GJ 1243 WITH KEPLER
We present an analysis of the starspots on the active M4 dwarf GJ 1243, using 4 years of time series photometry from Kepler. A rapid P = 0.592596 ? 0.00021 days rotation period is measured due to the
Photospheric and chromospheric activity in V405 Andromedae - An M dwarf binary with components on the two sides of the full convection limit
We investigate the fast-rotating (Porb = Prot = 0.465d), active dwarf binary V405 And (M0V+M5V) using photometric BV(RI)C and optical spectroscopic data. The light variation is caused by the combined
Powerful winds from low‐mass stars: V374 Peg
The M dwarf V374 Peg (M4) is believed to lie near the theoretical mass threshold for fully convective interiors. Its rapid rotation (P= 0.44 d) along with its intense magnetic field point towards
A search for flares and mass ejections on young late-type stars in the open cluster Blanco-1
We present a search for stellar activity (flares and mass ejections) in a sample of 28 stars in the young open cluster Blanco-1. We use optical spectra obtained with ESO's VIMOS multi-object
Kepler Flares I. Active and Inactive M dwarfs
We analyzed Kepler short-cadence M dwarf observations. Spectra from the ARC 3.5m telescope identify magnetically active (H$\alpha$ in emission) stars. The active stars are of mid-M spectral type,
Optical and X-ray studies of chromospherically active stars: FR Cancri, HD 95559 and LO Pegasi
We present a multiwavelength study of three chromospherically active stars, namely FR Cnc (= BD +16 ◦ 1753), HD 95559 and LO Peg (=BD +22 ◦ 4409), including newly obtained optical photometry,
Search for indications of stellar mass ejections using FUV spectra
Aims. We search for highly energetic activity phenomena in a small sample of late-type main-sequence stars in the far ultraviolet (FUV) using data from the Far Ultraviolet Spectroscopic Explorer
Photometric and spectroscopic observations of three rapidly rotating late-type stars: EY Dra, V374 Peg, and GSC 02038-00293†
a very rapidly rotating mid-K star. The Hline strength is variable, indicating changing chromosphe ric emission on GSC 02038-00293. In the case of EY Dra and V374 Peg, the stellar activity in the
Explaining the coexistence of large-scale and small-scale magnetic fields in fully convective stars
Despite the lack of a shear-rich tachocline region low-mass fully convective stars are capable of generating strong magnetic fields, indicating that a dynamo mechanism fundamentally different from
...
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