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Surveys of exoplanet host stars are valuable tools for assessing populationlevel trends in exoplanets, and their outputs can include stellar ages,activity, and rotation periods. We extracted chromospheric activitymeasurements from the California-Kepler Survey (CKS) Gaia survey spectra inorder to probe connections between stellar activity and fundamental stellarproperties. Building on the California Kepler Survey's legacy of 1189 planethost star stellar properties including temperature, surface gravity metallicityand isochronal age, we add measurements of the Ca II H and K lines as a proxyfor chromospheric activity for 879 planet hosting stars. We used thesechromospheric activity measurements to derive stellar rotation periods. We finda discrepancy between photometrically derived and activity-derived rotationperiods for stars on the Rossby Ridge. These results support the theory ofweakened magnetic braking. We find no evidence for metallicity-dependentactivity relations, within the metallicity range of -0.2 to +0.3 dex. With oursingle epoch spectra we identify stars that are potentially in Maunder Minimumlike state using a combination of log (R'HK) and position below themain-sequence. We do not yet have the multi-year time series needed to verifystars in Maunder Minimum like states. These results can help inform futuretheoretical studies that explore the relationship between stellar activity,stellar rotation, and magnetic dynamos.

The California-Kepler Survey. XI. A Survey of Chromospheric Activity Through the Lens of Precise Stellar Properties