OSCILLATIONS OF THE SUN CHROMOSPHERE - VIII - HORIZONTAL MOTIONS OF CA-II K BRIGHT POINTS

We present a re-analysis of a time series of solar disc centre Call K- 2 upsilon filtergrams taken with the Vacuum Tower Telescope at the Obs ervatorio del Teide/Tenerife. We concentrate on the measurements of pr oper motions of K grains in the internetwork regions and of bright poi nts in the chromospheric network. For the K grains we find horizontal velocities of 2-15 km s(-1), values much lower than those deduced by S teffens et al. (1996) from a smaller sample, analyzed differently. In accord with our earlier conclusion from kappa-omega diagrams (Kneer & von Uexkull 1993) and with numerical simulations by Carlsson & Stein ( 1997) high-frequency (pseudo-) p-modes can viably explain the K grains . Yet, the rareness of the K grains may indicate a connection to magne tic fields. The proper motions of the network bright points are non-pe riodic, very impulsive, with velocities of 7-10 km s(-1). Estimating t he energy flux if these motions are magnetic kink waves (cf. Choudhuri et al. 1993, Muller et al. 1994), we find it sufficient to heat the s olar corona, but too small to cover the radiative losses of the chromo spheric network.