Stellar-convection contamination of short-period radial-velocity signals

Determine whether stellar convection effects contaminate the coherent short-period radial-velocity signals attributed to the low-mass planet candidates around HD 67200 and HD 2134, and quantify any resulting bias in their inferred masses.

Background

The paper identifies moderate-evidence, short-period signals in HD 67200 and HD 2134 with amplitudes comparable to expected convective and supergranulation variability in low-activity stars. Although the signals persist over multi-year baselines, the authors caution that stochastic convection could contribute to their measured amplitudes.

If the observed radial velocities combine stellar-convection and Keplerian components, the inferred planetary masses could be biased, potentially upward. The contribution of convection therefore remains unresolved.

References

Coherent periodicities cannot be attributed to stochastic convective jitter, but we cannot rule out the possibility that the RVs are contaminated by stellar convection effects. Depending on exact periodicity interplay, one may expect masses to be overestimated if short period signals comprise both stochastic and Keplerian components.

— Three new exoplanet systems from the Dispersed Matter Planet Project  (2608.11902 - Barnes et al., 12 Aug 2026) in Section 5, Discussion