We have acquired high-resolution echelle spectra of 225 F6-M5 type stars in the southern hemisphere. The stars are targets or candidates to be targets for the Anglo- Australian Planet Search. CaII HK line cores were used to derive activity indices for all of these objects. The indices were converted to the Mt.Wilson system of measurements and logR′ HK values determined. A number of these stars had no previously derived activity indices. In addition we have also included the stars from Tinney et al. (2002) using our Mt. Wilson calibration. The radial-velocity instability (also known as jitter ) level was determined for all 21 planet-host stars in our dataset. We find the jitter to be at a level considerably below the radial-velocity signatures in all but one of these systems. 19 stars from our sample were found to be active (logR′ HK > -4.5) and thus have high levels of jitter. Radial-velocity analysis for planetary companions to these stars should precede with caution.
|Journal||Monthly Notices of the Royal Astronomical Society|
|Publication status||Published - 2006|