Data from "The Olin Wilson Legacy Survey (OWLS)"

The Olin Wilson Legacy Survey (OWLS; Morris et al 2025) presents spectroscopic observations from a planned 10 year survey of Ca II H & K emission, using observations made with the ARC 3.5m Telescope at Apache Point Observatory. The primary goal of the survey is to investigate activity cycles in low mass stars. The sample includes stars chosen from the legacy Mount Wilson survey carried out by Olin Wilson more than 50 years ago, together with newly identified planet-host stars and a select sample of early-mid M dwarfs. This collection of spectral time-series presents the first four years of data, with more than 1037 observations of 270 stars, with a specific focus on K and M stars. The team identifies a subsample of 153 stars for continuing observations over the full 10 year survey. The ultimate goal is to link the activity cycle and rotation periods in a robust sample of stars spanning FGKM spectral types and to investigate the implications for the underlying magnetic dynamo.