Stellar Rotation Studies
Stellar rotation is a fundamental tracer of stellar magnetic evolution, age, and activity. Measuring stellar rotation rates therefore offers us the chance to learn new information in multiple subfields of astronomy, and do things like find previously unidentified stellar populations and constrain exoplanet formation scenarios.
Filling the Gap: Calibrating Gyrochronology at 1.3 Gyr with the Benchmark Cluster NGC-752
Understanding the rotational evolution of main-sequence stars requires mapping stellar rotation as a function of mass and age. However, a key gap remains between well-studied ~1 Gyr and ~2.5 Gyr benchmarks, where few clusters have sufficiently characterized rotation sequences. This study helps fill that gap by using TARS periods to map, for the first time, the G- and K-dwarf rotation sequence of the ~1.3 Gyr open cluster NGC-752. The resulting sequence provides a new benchmark for tracing stellar spin-down through intermediate ages and for improving the calibration of gyrochronology models.
The TESS All-Sky Rotation Survey (TARS)
Click here for the paper and click here to play with the catalog
The TESS All-Sky Rotation Survey (TARS) provides rotation periods for almost a million stars with T < 16 within 500 pc of the Sun. Our rotation periods are derived from TESS Full Frame Images that cover sectors 1 -- 96. We additionally present a method to correct half-period aliases in TESS data, allowing us to recover rotation-temperature sequences of older open clusters and periods as long as 25 days from a single TESS sector.
Quantifying the Limits of TESS Stellar Rotation Measurements with the K2-TESS Overlap
What are the longest rotation periods we can reliably recover from a single TESS sector? What are the faintest stars for which we can reliably measure a rotation period with TESS? We answered these questions by comparing TESS-derived rotation periods to rotation periods derived for the same stars from K2, and found that TESS struggles to recover reliable rotation periods when the period is long (>13 days) or the star is faint (T > 16).