  We study the structure of the magnetic elements in network-cell interiors. A
quiet Sun area close to the disc centre was observed with the
spectro-polarimeter of the Solar Optical Telescope on board the Hinode space
mission, which yielded the best spatial resolution ever achieved in
polarimetric data of the Fe I 630 nm line pair. For comparison and
interpretation, we synthesize a similar data set from a three-dimensional
magneto-hydrodynamic simulation. We find several examples of magnetic elements,
either roundish (tube) or elongated (sheet), which show a central area of
negative Stokes-V area asymmetry framed or surrounded by a peripheral area with
larger positive asymmetry. This pattern was predicted some eight years ago on
the basis of numerical simulations. Here, we observationally confirm its
existence for the first time. We gather convincing evidence that this pattern
of Stokes-V area asymmetry is caused by the funnel-shaped boundary of magnetic
elements that separates the flux concentration from the weak-field environment.
We also conclude that this kind of magnetic element of the internetwork is
accompanied by electric current sheets.
