A 41-day GJ 3293 residual has gain ranges that include zero in 62 later HARPS velocities

We search for extra radial velocity signals in the public 2017 HARPS series of GJ 3293. A search from 2 to 1000 days in 145 early measurements selects a 41.135-day residual after four known planet periods and a linear trend are fitted. The fixed early wave reduces weighted error in 62 later measurements by 17.8 percent. All six conditional 95 percent block ranges include zero. The 30-day training and 30-day test range is -3.5 to 20.9 percent. Three block-sign search tests give conditional tail fractions from 0.068 to 0.242. Adding second harmonics of the known planets reduces the gain to 1.7 percent. The period is close to the known stellar rotation period. Another reduction gives positive point gains but shares 206 exposures. It also shows that a large change in reported line width depends on the data product. These results do not establish a new planet or a new physical cause. The later series spans only 172 days, and the known periods were selected with the full data. Code, exact inputs, source hashes, figures, controls, and offline steps are included.

astronomy · GJ 3293 · HARPS · radial velocity · stellar activity · residual search · time validation · null planet result