The age distribution of stars in the immediate solar environment

• Applicant: Professor Dr. Jürgen H.M.M. Schmitt
• Subject Area: Astrophysics and Astronomy
• Term: from 2015 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 283666120

Using our TIGRE telescope located in Guanajuato, Mexico, we have begun a systematic effort to determine the distribution of rotation velocities and ages of solar-like stars in the immediate solar environment. Age determinations for field stars are notoriously difficult and monitoring the core emission in the CaII 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. Starting in 2013, we have begun -- using TIGRE -- monitoring almost 100 nearby bright solar-like stars; within a given observing season we obtain typically 40 spectra per object, i.e., per observing season about 4000 spectra are available for analysis.In the context of this funding application we propose to carry out a thorough analysis of the existing data as well as the data to be taken in the next few seasons. In particular, systematic effects and errors will be investigated in a rigorous fashion. With the derived rotation periods we can perform gyro-chronology on our sample stars. Either with existing data or with data derivable from the TIGRE spectra the effective temperatures and chemical abundances fo the sample stars will be carried out; furthermore we will derive S-indices as well as lithium equivalent widths for all sample stars, and can thus 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.

• DFG Programme: Research Grants