A.S. Baran, M.D. Reed, R.H.Østensen, J.H. Telting, C.S. Jeffery, P. Németh

We present an analysis of the pulsating subdwarf B (sdB) star EPIC 203948264, observed during Campaign 2 of the extended Kepler mission. A time series analysis of the short cadence data set has revealed a rich g-mode pulsation spectrum with 20 independent pulsation periods between 0.5 and 2.8 hours. Most of the pulsations fit the asymptotic period sequences for ℓ = 1 or 2, with average period spacings of 261.34+/-0.78 and 151.18+/-0.34 s, respectively. The pulsation amplitudes are below 0.77 ppt and vary over time. Radial velocity measurements give no indication for binarity in this star. We did not find any clear rotationally induced pulsation multiplets, which indicates that the rotation period of the star is longer than about 46 days. By characterizing the various pulsation modes, we can constrain structural models of sdB stars. This is a promising approach to enhancing our understanding of horizontal branch stars.