Related papers: Living With a Red Dwarf: The Rotation-Age Relation…
The empirical relations between rotation period, chromospheric activity, and age can be used to estimate stellar age. To calibrate these relations, we present a catalog, including the masses and ages of 52,321 FGK dwarfs, 47,489…
The rotation periods of the host stars of extrasolar planets have been assessed against those of the Mt. Wilson stars, open cluster stars, and evolutionary stellar models that include rotation. They appear to be normal, modulo certain…
Context. M stars are preferred targets for studying terrestrial exoplanets, for which we hope to obtain their atmosphere spectra in the next decade. However, M dwarfs have long been known for strong magnetic activity and the ability to…
We review the current state of our knowledge concerning the rotation and angular momentum evolution of young stellar objects and brown dwarfs from a primarily observational view point. Periods are typically accurate to 1% and available for…
Red Dwarfs (main-sequence / dwarf M or dM) stars are the most common stars in the Galaxy. These cool, faint, low mass stars comprise over 75% of all stars. Because of their low luminosities (~0.0008-0.06 of the Sun's luminosity), the…
Observational tests of stellar and Galactic chemical evolution call for the joint knowledge of a star's physical parameters, detailed element abundances, and precise age. For cool main-sequence (MS) stars the abundances of many elements can…
The ages of the most common stars - low-mass (cool) stars like the Sun, and smaller - are difficult to derive because traditional dating methods use stellar properties that either change little as the stars age or are hard to measure. The…
We present a study of the dynamics and magnetic activity of M dwarfs using the largest spectroscopic sample of low-mass stars ever assembled. The age at which strong surface magnetic activity (as traced by H-alpha) ceases in M dwarfs has…
Stellar rotation periods are valuable both for constraining models of angular momentum loss and for under- standing how magnetic features impact inferences of exoplanet parameters. Building on our previous work in the northern hemisphere,…
Age is one of the most fundamental parameters of stars, yet it is one of the hardest to determine as it requires modelling various aspects of stellar formation and evolution. When we compare the ages derived from isochronal and dynamical…
We provide a status report on the determination of stellar ages from asteroseismology for stars of various masses and evolutionary stages. The ability to deduce the ages of stars with a relative precision of typically 10 to 20% is a unique…
We have examined the relationship between rotation and activity in 14 late-type (M6-M7) M dwarfs, using high resolution spectra taken at the W.M. Keck Observatory and flux-calibrated spectra from the Sloan Digital Sky Survey. Most were…
It is well established that activity and rotation diminishes during the life of sun-like main sequence (~F7-K2V) stars. Indeed, the evolution of rotation and activity among these stars appears to be so deterministic that their…
Stellar rotation is a strong function of both mass and evolutionary state. Missions such as Kepler and CoRoT provide tens of thousands of rotation periods, drawn from stellar populations that contain objects at a range of masses, ages, and…
We have examined the relationship between rotation and activity in 14 late-type (M6-M7) M dwarfs, using high resolution spectra taken at the Keck Observatory and flux-calibrated spectra from the Sloan Digital Sky Survey. Most are inactive…
Fully convective M dwarfs typically remain rapidly rotating and magnetically active for billions of years, followed by an abrupt and mass-dependent transition to slow rotation and quiescence. A robust understanding of this process is…
Age estimation techniques such as gyrochronology and magnetochronology can't be applied to stars that exchanged angular momentum with their close environment. This is especially true for massive close-in planetary companion (with a periods…
Rapidly rotating late M dwarfs are observed in two different branches of magnetic activity, although they operate in the same stellar parameter range. Current empirical evidence indicates that M dwarfs with spectral types ranging from M3 /…
Our ability to determine stellar ages from measurements of stellar rotation, hinges on how well we can measure the dependence of rotation on age for stars of different masses. Rotation periods for stars in open clusters are essential to…
The diversity of dynamical conditions among exoplanets is now well established. Yet, the relevance of orbital dynamical timescales to biological evolutionary timescales is poorly understood. Given that even minor orbital changes may place…