Horizontal motions in sunspot penumbrae

High-resolution observations of horizontal motions in the penumbra are needed to complement concept penumbrae obtained from spectropolarimetry. Time series intensity images a large sunspot AR 10634 acquired with Swedish Solar Telescope G band and red continuum analysed. The two simultaneous time last six hours five minutes. Horizontal penumbral grains (PGs), structures dark bodies filaments, outer border, G-band bright points measured slices that cover whole width neighbouring granulation. spatial temporal resolutions 90 km 20.1 s, respectively. In inner penumbra, PGs move toward umbra (inwards) mean speed -0.7 s-1. direction motion changes inwards outwards at approximately 60% increases gradually approaching 0.5 km/s. This is also typical an expansion penumbra-granulation border during periods typically one hour followed by fast contraction. majority moves away sunspot, 0.6 High outward speeds, 3.6 km/s on average, observed filaments. According model it suggested speeds detected filaments associated Evershed flow opposite directions PG may be explained interaction rising plasma filament heads surrounding, differently inclined magnetic field.