S-value for 59 Sun-like starswith HIRES and HKP

These include and extend the 35yr of stellar chromospheric activity observations by the Mount Wilson Survey (1966-2001), and continued observations at Keck by the California Planet Search (1996-). The Mount Wilson Survey was studied closely in 1995, and revealed periodic activity cycles similar to the Sun's 11yr cycle.

The California Planet Search provides more than five decades of measurements, significantly improving our understanding of these stars' activity behavior. We have curated the activity measurements in order to create contiguous time series, and have classified the stellar sample according to a predetermined system. We have analyzed 29 stars with periodic cycles using the Lomb-Scargle periodogram, and present best-fit sinusoids to their activity time series.