DOT study of dynamic fibrils in plage

J. Koza (1,2), P. Sütterlin (1), A. Kučera (2), J. Rybák (2)
(1) Sterrekunding Instituut, Utrecht University, The Netherlands
(2) Astronomical Institute, Slovak Academy of Sciences, Tatranská Lomnica, Slovakia

We present kinematic parameters of fibrils observed in an isolated plage. We analyse the 10-min image sequence obtained by the Dutch Open Telescope (DOT) in the blue flank of the H? line during the best seeing ever recorded by DOT up to now. Tops of the fibrils follow trajectories suggesting parabolic motion with typical deceleration of 150 m s-2. Initial impulse uplifts the chromospheric plasma with supersonic velocities larger than 20 km s-1. We interpret the sideways drift of fibrils as turning motion with typical angular velocity of 2.7 deg min-1. Sense of turning is the same for almost all fibrils suggesting some relation to the large-scale motions in the plage. However, the angular velocity of this motion decreases with length of fibril.