Meridional and equatorial center-to-limb variation of the asymmetry and shift of three Fe I solar photospheric lines around 6300 A

In this paper we describe an investigation on the center-to-limb variation of the line asymmetry and shift along the polar and equatorial diameters of the Sun, carried out on the Fe I photospheric lines at 6297.8 Å, 6301.5 Å, and 6302.5 Å. In particular we aim at ascertaining how much of the so called meridional motion is due to a possible latitudinal dependence of the convection, and how much to real large scale mass flows. The observations, obtained with the Fabry-Perot spectrointerferometer installed at the Donati Solar Tower in Arcetri, do not show any significant latitudinal effect on the line bisector shapes. The results regarding the latitudinal dependence of the limb shift are ambiguous.