Correlations between HARPS (HAM) RVs and its ΔT indicator (left) and with the d ΔT/d t (right). The blue data points show the RVs that include the 16-day signal and the orange data points show the RVs after removing the best-fit Keplerian model of the 16-day signal. A linear function is fitted in each dataset. First-order correlation (top): R=−0.135 to R=−0.238 and N_σ=2.71 to N_σ=6.73. Second-order correlation (bottom): R=−0.386 to R=−0.479 and N_σ=17.2 to N_σ=20.6