Nine-pixel apertures reduce the KIC 8164262 amplitude excess in two Kepler quarter pairs

We test whether a known oscillation has the same measured fractional amplitude in different pixel apertures. We use Kepler release 25 pixels for KIC 8164262 in quarters 4, 5, 8, and 9. Relative to the mission aperture, the nine brightest pixels reduce the quarter 4 minus quarter 5 amplitude difference by 12.35 +/- 2.09 parts per million. They reduce the quarter 8 minus quarter 9 difference by 13.78 +/- 2.36 parts per million. The errors use paired two-day residual blocks and do not include calibration errors. A second baseline fit gives the same direction and similar sizes. The result shows that aperture choice affects the measured quarter differences. It does not prove an instrument cause or remove all of the difference. We report no new planet or stellar mode. The package has code, accepted pixels, source hashes, tables, and figures.

astronomy · Kepler · KIC 8164262 · tidal oscillation · aperture photometry · instrument response