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In this work we consider the sensitivity of gravity-mode period spacings to sharp changes in the inner structure of red giant stars, more specifically in the buoyancy frequency inside the g-mode propagation cavity. Based on a comparison between the solutions to the linear pulsation equations in the Cowling approximation for pure g-modes with results obtained with a full oscillation code we identify and correctly interpret the signature of the above-mentioned sharp variations in the period spacings. Two examples, of red giant models in different evolutionary phases, are discussed. Detection of these signatures in CoRoT, Kepler or future PLATO red-giant stars would pin down their evolutionary state in an unprecedented way. [ABSTRACT FROM AUTHOR]

We present an asteroseismic approach to study the dynamics of the stellar interior in red giant stars by asteroseismic inversion of the splittings induced by the stellar rotation on the oscillation frequencies. We show preliminary results obtained for the red giant KIC4448777 observed by the space mission Kepler. [ABSTRACT FROM AUTHOR]

The asteroseismic scaling relations for the frequency of maximum oscillation power, vmax, and the large frequency separation, Δν, provide an easy way to directly determine the masses and radii of stars with detected solar-like oscillations. With the vast amount of data available from the CoRoT and Kepler missions, the convenience of the scaling relations has resulted in their wide-spread use. But how valid are the scaling relations when applied to red giants, which have a substantially different structure than the Sun? Verifying the scaling relations empirically requires independent measurements. We report on the current state and future prospects of interferometric tests of the scaling relations. [ABSTRACT FROM AUTHOR]

We present preliminary results of an asteroseismic analysis of the open clusters NGC 6791 and NGC 6819 in the Kepler field of view. We analysed over 400 stars to extract the asteroseismic properties νmax and Δν to make them available to the scientific community. We developed an interactive stitching algorithm that is used to correct for the instrumental drifts in the Kepler light curves and stitch the jumps between each quarter together. We use the SYD pipeline to extract the asteroseismic values and compare these to the expected values for cluster membership to find new member stars for each cluster. We compare our results to previous membership studies. [ABSTRACT FROM AUTHOR]