No extra 5 to 1000 day wave passes a 1 percent full-search threshold in 31 Kapteyn HIRES nights

We search 31 public HIRES nights of Kapteyn's star for an extra wave after a free fit at the reported 48.616 and 121.54 day periods. A search at 5444 frequencies from 5 to 1000 days gives a strongest peak at 17.55 days. It removes 49.7 percent of residual weighted squared error, but its full-search tail fraction is 0.532 in 4095 trials with 30-day residual sign blocks. Gaussian, night, and year trials also give no detection. Weight, instrument-step, and linear activity controls give tail fractions from 0.200 to 0.647. Conditional trials recover the correct frequency in only 7.4 to 10.2 percent of 4 m/s injections at four periods, but in 96.5 to 100 percent of 8 m/s injections. Thus the null result does not exclude small planets. The sign model assumes symmetric noise in independent bins and does not cover all stellar activity. Code, aggregate results, simulated scores, input hashes, and retrieval steps are included. External observation tables are excluded.

astronomy · Kapteyn star · HIRES · radial velocity · residual search · null result · injection recovery · search trials