probabilistic modeling of eclipses

Here is a GALEX eclipse with 64 posterior samples from a probabilistic model superimposed.

The star looks slightly variable out of eclipse because there is a varying background superimposed on the stellar light; this is part of the model too if you are doing proper Poisson likelihoods (as we are). Thanks to Foreman-Mackey for the awesome emcee sampler and Dave Spiegel (IAS) for some great (because it is so simple) transit-modeling code.

Not surprisingly, there is some degeneracy between the inferred impact parameter and the inferred ratio of radii of the star and companion. But it looks like we will be able to say things about the companion radii.

No comments:

Post a Comment