10 Years of Stellar Activity for GJ 1243. (arXiv:2005.10281v1 [astro-ph.SR])
<a href="http://arxiv.org/find/astro-ph/1/au:+Davenport_J/0/1/0/all/0/1">James. R. A. Davenport</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mendoza_G/0/1/0/all/0/1">Guadalupe Tovar Mendoza</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hawley_S/0/1/0/all/0/1">Suzanne L. Hawley</a>

The flaring M4 dwarf GJ 1243 has become a benchmark for studying stellar
flare and starspot activity thanks to the exceptional photometric monitoring
archive from the Kepler mission. New light curves from the TESS mission for
this star allow precise stellar activity characterization over more than a
decade timescale. We have carried out the first flare and starspot analysis of
GJ 1243 from over 50 days of data from TESS Sectors 14 and 15. Using 133 flare
events detected in the 2-minute cadence TESS data, we compare the cumulative
flare frequency distributions, and find the flare activity for GJ 1243 is
unchanged between the Kepler and TESS epochs. Two distinct starspot groups are
found in the TESS data, with the primary spot having the same rotational period
and phase as seen in Kepler. The phase of the secondary spot feature is
consistent with the predicted location of the secondary starspot and
measurement of weak differential rotation, suggesting this secondary spot may
be long-lived and stable in both latitude and longitude. As expected for this
highly active star, the constant spot and flare activity reveal no sign of
solar-like activity cycles over 10 years. However, we highlight the unique
ability for Kepler and TESS to use flare rates to detect activity cycles.

The flaring M4 dwarf GJ 1243 has become a benchmark for studying stellar
flare and starspot activity thanks to the exceptional photometric monitoring
archive from the Kepler mission. New light curves from the TESS mission for
this star allow precise stellar activity characterization over more than a
decade timescale. We have carried out the first flare and starspot analysis of
GJ 1243 from over 50 days of data from TESS Sectors 14 and 15. Using 133 flare
events detected in the 2-minute cadence TESS data, we compare the cumulative
flare frequency distributions, and find the flare activity for GJ 1243 is
unchanged between the Kepler and TESS epochs. Two distinct starspot groups are
found in the TESS data, with the primary spot having the same rotational period
and phase as seen in Kepler. The phase of the secondary spot feature is
consistent with the predicted location of the secondary starspot and
measurement of weak differential rotation, suggesting this secondary spot may
be long-lived and stable in both latitude and longitude. As expected for this
highly active star, the constant spot and flare activity reveal no sign of
solar-like activity cycles over 10 years. However, we highlight the unique
ability for Kepler and TESS to use flare rates to detect activity cycles.

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