On the Evolution of Point-like Convective Collapse Events Seen in High-Resolution Photospheric and Chromospheric Filtergrams of Hinode/SOT

The formation of small-scale strong magnetic features in the quiet Sun was studied for a long time. It is likely that magnetic field on the solar surface is collected in the intergranular lanes by the horizontal flows in granules, and then a convective instability (collapse), which leads to downflow in the flux tube and a reduction of the internal gas pressure, intensifies them to kG levels. However, a static equilibrium with such a strong field would not be realized and open question remained is the evolution including the possible rebounding upflow and the associated chromospheric responses, which may show up as shocks and subsequent heating. Using high resolution time series of Hinode/SOT filter images in Na D1 line and Ca II H band at the quiet Sun disk center, we were able to identify many point-like convective collapse events in the photosphere and corresponding chromospheric bright points. For each events, we determined the duration, photospheric vertical flow velocities, line-of-sight field strength increase and the signature of chromospheric brightening. We present the implications of convective collapse on the photospheric and chromospheric dynamical processes.