A seasonal fit gives a 0.78 m/s GJ 176 velocity difference, but long-bin evidence depends on bin origin

We test DRS minus SERVAL velocities for GJ 176 in 115 selected HARPS-RVBank version 02 visits. A seasonal rotation model gives a common 8.776-day difference amplitude of 0.781 m/s. Conditional residual sign tests give upper-tail fractions of 0.0025 to 0.01325 for four bin lengths. A half-bin shift raises the 100-day fraction to 0.062. Before nightly corrections, the amplitude is 0.490 m/s and the 100-day fraction is 0.071. A fixed differential wave raises held-season error in two of seven seasons. Thus evidence depends on calibration and error rules. Shared spectra, unknown paired error covariance, sparse seasons and prior period selection limit the result. No new planet, secure instrument fault, or independent confirmation is found. Code, aggregate results, a figure, exact source provenance and hash-checked repeat steps are included. The external database is excluded.

astronomy · GJ 176 · HARPS · velocity extraction · SERVAL · nightly correction · conditional test