Evidence for at least three planet candidates orbiting HD20794

摘要: We explore the feasibility of detecting Earth analogs around Sun-like stars using radial velocity method by investigating one largest velocities datasets for most stable radial-velocity HD20794. proceed disentangling Keplerian signals from correlated noise and activity-induced variability. diagnose differences between measured at different wavelength ranges, so-called "differential velocities". apply this to HARPS, identify four 18, 89, 147 330 d. The two periods 18 89 d are previously reported better quantified in work. signal a period about is first time, corresponds super-Earth with minimum mass 4.59 located 0.51 AU also find significant corresponding or Neptune habitable zone. Since close annual sampling periodogram power some proxies found signal, further observations analyses required confirm it. eccentricity consistency provide weak evidence existence 43 new 11.9 semi amplitude 0.4 m/s. that detection number variations 0.5\,m/s likely caused low planet candidates demonstrates important role modeling searching analogs.