Maximizing Kepler science return per telemetered pixel: Detailed models of the focal plane in the two-wheel era

David W. Hogg; Ruth Angus; Tom Barclay; Rebekah Dawson; Rob Fergus; Dan Foreman-Mackey; Stefan Harmeling; Michael Hirsch; Dustin Lang; Benjamin T. Montet; David Schiminovich; Bernhard Schölkopf

arXiv · 1309.0653

Maximizing Kepler science return per telemetered pixel: Detailed models of the focal plane in the two-wheel era

David W. Hogg·Ruth Angus·Tom Barclay·Rebekah Dawson·Rob Fergus·Dan Foreman-Mackey·Stefan Harmeling·Michael Hirsch·Dustin Lang·Benjamin T. Montet·David Schiminovich·Bernhard Schölkopf

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Abstract

Kepler's immense photometric precision to date was maintained through satellite stability and precise pointing. In this white paper, we argue that image modeling--fitting the Kepler-downlinked raw pixel data--can vastly improve the precision of Kepler in pointing-degraded two-wheel mode. We argue that a non-trivial modeling effort may permit continuance of photometry at 10-ppm-level precision. We demonstrate some baby steps towards precise models in both data-driven (flexible) and physics-driven (interpretably parameterized) modes. We demonstrate that the expected drift or jitter in positions in the two-weel era will help with constraining calibration parameters. In particular, we show that we can infer the device flat-field at higher than pixel resolution; that is, we can infer pixel-to-pixel variations in intra-pixel sensitivity. These results are relevant to almost any scientific goal for the repurposed mission; image modeling ought to be a part of any two-wheel repurpose for the satellite. We make other recommendations for Kepler operations, but fundamentally advocate that the project stick with its core mission of finding and characterizing Earth analogs. [abridged]

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David W. Hogg, Ruth Angus, Tom Barclay, Rebekah Dawson, Rob Fergus, Dan Foreman-Mackey, Stefan Harmeling, Michael Hirsch, Dustin Lang, Benjamin T. Montet, David Schiminovich, Bernhard Schölkopf. 2013-09-03. Maximizing Kepler science return per telemetered pixel: Detailed models of the focal plane in the two-wheel era. https://arxiv.org/abs/1309.0653

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