  A qualitative analysis is given to the data on the full magnetic and velocity
vector fields in a growing sunspot group, recorded nearly simultaneously with
the Solar Optical Telescope on the Hinode satellite. Observations of a young
bipolar subregion developing within AR 11313 were carried out on 9-10 October
2011. Our aim was to form am idea about the consistency of the observed pattern
with the well-known rising-tube model of the formation of bipolar acrive
regions and sunspot groups. We find from our magnetograms that the
distributions of the vertical [B_v] and the horizontal [B_h] component of the
magnetic field over the area of the magnetic subregion are spatially well
correlated; in contrast, the rise of a flux-tube loop would result in a
qualitatively different pattern, with the maxima of the two magnetic-field
components spatially separated: the vertical field would be the strongest where
either spot emerges, while the maximum horizontal-field strengths would be
reached in between them. A specific feature, which we call the bordering
effect, is revealed: some local extrema of B_v are bordered with areas of
locally enhanced B_h. This effect suggests a fountainlike spatial structure of
the magnetic field near the B_v extrema, which is also hardly compatible with
the emergence of a flux-tube loop. The vertical-velocity field in the area of
the developing active subregion does not exhibit any upflow on the scale of the
whole subregion, which should be related to the rising-tube process. Thus, our
observational data can hardly be interpreted in the framework of the
rising-tube model.

Solar and Stellar Astrophysics