Quarter orbital fits remove over 99 percent of a test frequency sweep in KIC 3230227 sampling

We test loss of a constant-amplitude signal whose frequency crosses the 13th orbital harmonic at BKJD 850. The test uses public Kepler release 25 sample times for KIC 3230227. With a drift of 0.000001 cycles per day squared and 40 orbital harmonics fitted separately in each quarter, the full data retain 0.00406 to 0.00409 of signal energy over all phases. Quarter 9 retains only 0.0000066 to 0.0000069. A joint fit recovers added coefficients in a no-noise check. The result gives a search-method check for signals with changing frequency. It does not show a frequency sweep in the star, a new mode, or a planet. It does not test instrument corrections or real noise.

Kepler · KIC 3230227 · frequency drift · orbital subtraction · signal loss