Gavin Ramsay, J. Gerry Doyle

The M4.5V flare star AF Psc as seen in K2 engineering data

Figure 1. The light curve of AF Psc made using K2 in engineering data where each point has an effective exposure of 29 min. The data has been phased (φ=0.0 is defined by minimum flux) on the 1.08 day period which is clearly present in the data. The vertical lines at the top of the panel note the time of flares in the light curve. The three consecutive flares occuring at φ ∼0.12 are noted by dashed vertical lines.


We present the light curve of the little studied flare star AF Psc (M4.5V) obtained using engineering data from the K2 mission. Data were obtained in Long Cadence mode giving an effective exposure of 29 min and nearly 9 d of coverage. A clear modulation on a period of 1.08 d was seen which is the signature of the stellar rotation period. We identify 14 flares in the light curve, with the most luminous flares apparently coming from the same active region. We compare the flare characteristics of AF Psc to two M4V flare stars studied using Kepler data. The K2 mission, if given approval, will present a unique opportunity to study the rotation and flare properties of late type dwarf stars with different ages and mass.

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Last Revised: 2014 May 29th