Kepler super-flare stars: what are they?

Abstract

The Kepler mission has led to the serendipitous discovery of a significant number of `super flares' - white light flares with energies between 10^33 erg and 10^36 erg - on solar-type stars. It has been speculated that these could be `freak' events that might happen on the Sun, too. We have started a programme to study the nature of the stars on which these super flares have been observed. Here we present high-resolution spectroscopy of 11 of these stars and discuss our results. We find that several of these stars are very young, fast-rotating stars where high levels of stellar activity can be expected, but for some other stars we do not find a straightforward explanation for the occurrence of super flares.

arXiv commentAccepted for publication in A&A, 9 pages, 4 figures

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Cited by in corpus (13)

• Statistical properties of superflares on solar-type stars based on 1-min cadence data
• From coronal observations to MHD simulations, the building blocks for 3D models of solar flares
• Extreme solar events
• Do Kepler superflare stars really include slowly-rotating Sun-like stars ? - Results using APO 3.5m telescope spectroscopic observations and Gaia-DR2 data -
• Modeling Stellar Proton Event-induced particle radiation dose on close-in exoplanets
• Simultaneous Kepler/K2 and XMM-Netwon observations of superflares in the Pleiades
• High Dispersion Spectroscopy of Solar-type Superflare Stars. I. Temperature, Surface Gravity, Metallicity, and $v\sin i$
• Do long-cadence data of {\it Kepler} satellite capture the basic properties of flares ?
• Supernovae and Single-Year Anomalies in the Atmospheric Radiocarbon Record
• High Dispersion Spectroscopy of Solar-type Superflare Stars. III. Lithium Abundances
• Variations of 14-C around AD 775 and AD 1795 - due to solar activity
• Variability induced motion in Kepler data
• KIC011764567: An evolved object showing substantial flare-activity