Velocity Field in Intergranular Atmosphere

The line-of-sight velocity vl and macroturbulent velocity vm are studied in the center of the intergranular space in solar photosphere. An inversion meth od is applied to a 4-min time sequence of Stokes I spectra of the Fe I 522.5nm and Fe I 557.6nm and Fe I 557.7nm lines observed with high spatial and temporal resolutions at solar disk center. The results are presented in the form of the functional dependence of vl (log(tau_5),t) and vm(t) on the continuum optical depth tau_5 at 500nm and time t. A vl several hundreds of meters per second was found in the upper photosphere (log(tau_5)<=-1.5), where the plasma flows away from the observer. On the contrary, upflows directing toward the observer were found in deeper layers (log(tau_5)>-1.5). The typical value of vm in the center of the intergranular space is found to be ~1.7km/s, which is about 0.5 km/s greater than in the adjacent granule.