Searching for Stellar Activity Cycles using Flares

We examine 4 years of Kepler 30-min data, and 5 Sectors of TESS 2-min data for the dM3 star KIC 8507979/TIC-272272592. This rapidly rotating (P=1.2 day) star has previously been identified as flare active, with a possible long-term decline in its flare output. Such slow changes in surface magnetic activity are potential indicators of Solar-like activity cycles. We find that KIC 8507979 shows both short and long timescale variations in its flare activity that are larger than expected from the power-law flare occurrence distribution. Only a handful of stars have been subjected to such long baseline point-in-time flare studies. We believe this is powerful new method for measuring the months-to-years changes in surface magnetic activity, and to provide important constraints on activity cycles and dynamo models for low mass stars.