CoRoT Symposium 3, Kepler KASC-7 joint meeting
6-11 Jul 2014 Toulouse (France)

Abstracts > Jones Caitlin

Ensemble Testing of Asteroseismic Scaling Relations for Stellar Population Studies
Caitlin Jones  1@  , William Chaplin  1@  , Yvonne Elsworth  1  , Andrea Miglio  1  
1 : School of Physics and Astronomy, University of Birmingham
Edgbaston, Birmingham B15 2TT, UK -  United Kingdom

Using a simulated Kepler field created by the TRILEGAL code, and various existing scaling relations for the maximum oscillation intensity amplitude (Amax) of red giant stars, we estimate, for each scaling relation a signal-to-noise ratio for the oscillations assuming a Harvey-like profile for the granulation power and a Gaussian envelope modulating the oscillation power. We would expect the simulated SNR to be virtually independent of numax for stars in the long cadence frequency range, as is the case for Kepler observations. Here, we use tests against the observations to determine the most suitable scaling relation to use in further work with both synthetic and observational data for stellar population studies.

We also use a band-pass-filtered estimate of the variance of the Kepler lightcurves of red-giant stars, a measure dominated by the combined signal due to oscillations and granulation, and find that it provides a sensitive way to discriminate red giants in different evolutionary states (in particular separating out stars in the secondary clump). Our eventual aim will be to use the variance metric as a tool to identify signatures of binarity in the ensemble population.

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