Measurements of rotation and turbulence in F, G, and K dwarfs

Abstract

Spectral line broadening in 18 F, G, and K dwarfs is analyzed for rotation and macroturbulence. Zeeman broadening is shown to have a significant effect on the derived parameters in late G and early K dwarfs. Support is found for the traditional (lower) v sin i scale. The rotation of the sun is probably normal compared to other stars. The average macroturbulence velocity decreases rapidly with advancing spectral type at the rate of 4 km/s per thousand degrees of effective temperature. The macroturbulence velocity is proportional to the granulation velocities for F and G stars.