Document Type

Article

Publication Date

12-8-2014

Keywords

Stars: activity, Stars: flare, Stars: low-mass

Abstract

We present the largest sample of flares ever compiled for a single M dwarf, the active M4 star GJ 1243. Over 6100 individual flare events, with energies ranging from 1029 to 1033 erg, are found in 11 months of 1 minute cadence data from Kepler. This sample is unique for its completeness and dynamic range. We have developed automated tools for finding flares in short-cadence Kepler light curves, and performed extensive validation and classification of the sample by eye. From this pristine sample of flares we generate a median flare template. This template shows that two exponential cooling phases are present during the white-light flare decay, providing fundamental constraints for models of flare physics. The template is also used as a basis function to decompose complex multi-peaked flares, allowing us to study the energy distribution of these events. Only a small number of flare events are not well fit by our template. We find that complex, multi-peaked flares occur in over 80% of flares with a duration of 50 minutes or greater. The underlying distribution of flare durations for events 10 minutes and longer appears to follow a broken power law. Our results support the idea that sympathetic flaring may be responsible for some complex flare events.

Publication Title

The Astrophysical Journal

Volume

797

Issue

2

First Page

122

DOI

10.1088/0004-637X/797/2/122

Required Publisher's Statement

Published 2014 December 8 • © 2014. The American Astronomical Society. All rights reserved.

Link to journal article: http://iopscience.iop.org/article/10.1088/0004-637X/797/2/122

DOI: http://dx.doi.org/10.1088/0004-637X/797/2/122

Subjects - Topical (LCSH)

Stars--Activity; Stars--Magnetic fields; Stars--Observations

Genre/Form

articles

Type

Text

Language

English

Format

application/pdf

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