finding tiny planets, Kepler jumps, papers

Foreman-Mackey and I had a long and wide-ranging conversation about exoplanet search. He has search completeness in regimes of exoplanet period heretofore unexplored, and more completeness at small radii than anyone previously, as far as we can tell. However, his search still isn't as sensitive as we would like. We are doing lots of hacky and heuristic things ("ad hockery" as Jaynes and Rix both like to say), so there is definitely room for improvement. All that said, we might find a bunch of smaller and longer-period planets than anyone before. I am so stoked.

In related news, we looked at a Kepler star that suffered an instantaneous change in brightness. We went back to the pixel level, and found the discontinuity exists in every pixel in the star's image, but the discontinuity has different amplitudes including different signs in the different pixels. It is supposed to be some kind of CCD defect, but it is as if the star jumped in position (but its fellow stars on the CCD didn't). It is just so odd. When you do photometry at this level of precision, so many crazy thing appear.

Late in the day I caught up on reading and commenting on papers people have sent me, including a nice paper by Megan Shabram (PSU) et al on a hierarchical Bayesian model for exoplanet eccentricities, a draft paper (with my name on it) by Jessi Cisewski (CMU) et al on likelihood-free inference for the initial mass function of stars, a draft paper by Dustin Lang (CMU) and myself on principled probabilistic source detection, a paper by John Jenkins (Ames) et al on optimal photometry from a jittery spacecraft (think Kepler), and the draft paper by Melissa Ness et al on The Cannon.

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