MgIb(2) bright features in the solar photosphere

The magnetic network is a key component of solar irradiance and of the energy transport toward the corona. These network structures are associated in the photosphere with bright magnetic elements, whose dynamics is determined by granulation. The association between small magnetic elements and bright points in the photosphere, which are cospatial with magnetic network (e.g. Muller et al., 2000, or Baudin et al., 1997), allow us the selection of magnetic regions of interest for a spectroscopic study. The photospheric magnetic network contribution to the Total Solar Irradiance (TSI) and its variations is a still open problem even if it has been discussed in different papers (e.g. Unruh, Solanki and Fligge, 1999, or Schuhle et al., 2000). Recently, by analyzing full-disk RISE-PSPT observations, it has been evaluated the photospheric network contrast and the role of related variations to the TSI (Ermolli, Berrilli and Florio, 1999). In this paper we present an analysis of properties of photospheric vertical velocity and broad band intensity Fields associated to bright MgIb(2) elements. The observations of a central quiet granulation field were obtained with the THEMIS-IPM using the Fel 557.6 nm and MgIb2 517.3 nm lines.