Talk

Rotation and ages of stars in the immediate solar environment

Jürgen Schmitt, Hamburger Sternwarte

Age determinations for field stars are notoriously difficult and monitoring the core emission in the Ca~II H&K lines is one of the few methods available to determine the rotation rates of solar-like stars at rather low levels of activity. Using the now released Mount Wilson data as well as our own data collected with our robotic TIGRE telescope located in Guanajuato, Mexico, we have begun a systematic effort to determine the distribution of rotation velocities and ages of a complete sample of solar-like stars in the immediate solar environment. Such nearby stars have the great advantage that can also be studied in other wavelength bands such as the X-ray range, so a complete picture of their activity properties can be derived. With the collected data we can derive S-indices as well as lithium equivalent widths for all sample stars, and can perform a comprehensive assessment of the ages of the sample stars through gyro-chronology, isochrone placement on evolutionary tracks as well activity indicators and lithium strength.