Histogram of the parameters of the Fe line when fitted with a Gaussian component for the full sample considered in this work. The white rectangles marked with an arrow correspond to the lines detected below a significance of 3 σ (see Fig. 5). The width (middle panel) and the EW (right panel) have a well-defined “Gaussian-like” distribution around the weighted average value, while the outliers have large errors associated to their σ and EW values.