Exponential scale lengths of the Lyα haloes plotted against a) total Lyα luminosities; b) absolute UV continuum magnitudes; c) total Lyα rest frame equivalent widths. Lower limits on M_UV are indicated by arrows. The crossed circles give the mean values of each quantity in our sample (separately for EW_t< 100 Å and EW_t> 100 Å in panel c)). Other coloured symbols show values from the literature based on the stacking of narrowband images – green filled circles: Steidel et al. (2011, ⟨z⟩ = 2.65, magenta filled triangles: Feldmeier et al. (2013, C-O3 subsample, z = 3.1, blue open squares: Momose et al. (2014, z = 3.1.