On the microturbulence in the solar photosphere

Abstract

The velocity of microturbulent motions in the solar photosphere at the level of formation of weak Fraunhofer lines (h ∼ 150 km) is found to be 0.1 ± 0.2 km s−1. The observations have been performed with the double-pass spectrometer in Kiev. Apart from thermal motions and damping effects we have taken into account convective and wave motions when calculating the broadening of absorption lines.