The delta Scuti pulsator occurrence as a function of age, T eff, rotation, and metallicity

Many A- and F- type stars do not display delta Scuti pulsations, despite being located within the instability strip. We use photometry from the TESS Mission to discover and study delta Scuti pulsators in open clusters within 500 pc and with ages between 20 and 900 Myr, which provide a unique opportunity to study delta Scuti pulsators in coeval populations with uniform chemical composition. We measure pulsator occurrence, which corrects the pulsator fraction for incompleteness, across all clusters. We find that clusters younger than 200 Myr tend to exhibit higher occurrence rates, with an average occurrence of 88 plus or minus 3%. The occurrence rates in clusters older than 200 Myr tend to resemble the pulsator fraction of field-star samples, with an average occurrence of 62 plus or minus 3%. In addition, we find that pulsators tend to rotate more rapidly in older clusters than their younger counterparts and that hotter pulsators may stop pulsating earlier than their cooler counterparts. These results show that pulsator occurrence decreases with age and that rapid rotation is critical in maintaining delta Scuti pulsations over time.