English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present the flare occurrence rates and starspot evolution for GJ 1245 Aand B, two active M5 stars, based on nine months of Kepler short cadenceobservations, and four years of nearly continuous long cadence observations.The A component is separated from the B component by 7 arcseconds, and thestars are not resolved in the Kepler pipeline processing due to Kepler's largeplate scale of 4 arcseconds/pixel. Analyzing the target pixel data, we havegenerated separate light curves for components A and B using the PyKE pixelresponse function modeling procedures, and note the effects of CCD saturationand non-linear response to high energy flares. In our sample, GJ 1245A and Bexhibit an average of 3.0 and 2.6 flares per day, respectively. We introduce anew metric, $L_{fl}/L_{\mathrm{Kp}}$, to compare the flare rates between stars,and discuss this in the context of GJ 1245 A and B. Both stars exhibit starspotfeatures that evolve on long time scales, with the slower rotating B componentshowing evidence of differential rotation. Intriguingly, the angular separationbetween the A and B component photocenters decreases during the four years ofobservations in a manner consistent with a shift in the position of the Aphotocenter due to the orbit of its unseen M8 companion (GJ 1245C), which is$\sim$94% less bright. Among the most detailed photometric studies of fullyconvective M dwarfs in a multiple system, these results provide an importantconstraint on stellar age-rotation-activity models.

Kepler Flares III: Stellar Activity on GJ 1245 A and B