An early 34.62-day wave increases later fit error in 232 pre-upgrade HARPS nights of HD 40307

We test the proposed HD 40307 e signal in public HARPS-RVBank version 02. A circular wave fitted to 137 early nights increases weighted error in 95 later nights by 7.77 percent in SERVAL and 8.75 percent in DRS. Conditional 30-day residual-sign intervals are -24.98 to 3.76 percent and -25.94 to 1.16 percent. Both include zero gain. All 72 tested trend, outer-wave, period and velocity-product settings give negative gain. An early-only period search selects 34.77 days and also gives negative later gain. Activity and Earth-velocity terms retain the negative point gain. At a fixed 34.62-day period, injected 1 m/s coherent waves pass a conditional 99th-percentile noise threshold in 85.6 to 89.6 percent of trials. We do not confirm or exclude a planet. Fixed periods, selected models, correlated noise, and shared instrument data limit the result. Code, aggregate results, a figure, source hashes, and external retrieval steps are included. No new planet or unique physical cause is found.

astronomy · HD 40307 · radial velocity · planet candidate · time validation · null result · HARPS