As my loyal reader knows, I have four separate projects with Bonaca, Feeney, Casey, and Bedell to forward-model asteroseismic modes, with Bonaca concentrating on ground-based data, Feeney on principled Bayes, Casey on ESA Gaia, and Bedell on removing the modes as nuisances when we want to find planets. Today Bedell and I discussed where we are at, and came up with some things to try. In Sun-like stars, the modes have days-ish coherence times (apparently) and the modes have minutes-ish periods. So there are different regimes as your exposure cadence ranges from minutes to days to weeks. We have some qualitative predictions, and we are trying to make quantitative results that will influence survey design in the near future (especially for Terra Hunting Experiment and NASA NEID).
One funny thing about quasi-periodic (as in: finite coherence-time) oscillation processes is that they can be generated as a subset of Gaussian Processes, if you have good kernel machinery. We do! Another funny thing is that a GP can fit anything it is asked to fit! It literally has infinity free parameters (yes, literally). But the more appropriate kernels will do better (we hope) at predicting held-out data.
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