  A cancellation is thought to be a basic process of the photospheric magnetic
field and plays an important role in magnetic flux budget and in various solar
activities. There are two major theoretical scenarios for this phenomena, i.e.
the "U-loop emergence" and the Omega-loop submergence models. It is important
to clarify which is the dominant process during the cancellation for the
estimation of the solar magnetic flux transport through the surface. We study
the vector magnetic field and velocity structures around a quiet Sun
cancellation by using the Solar Optical Telescope on board Hinode satellite.
Transverse magnetic field connecting the canceling magnetic features and strong
long-lasting Doppler red-shift signal are found. The transverse field is
observed in the first spectropolarimetric observation after the occurrence of
the cancellation while the red-shift clearly delayed to the cancellation by 20
minutes. These results indicate that the observed cancellation is an Omega-loop
submergence.
