Left: Lyα surface brightness, I(r), of the z ~ 2 LARS-LAE and LARSaverage stacks, before convolution with ground-based PSF (cyan circles and blue triangles). The PSF-convolved LARS-LAE stack is shown with the cyan line. The ground-based PSF profile from Feldmeier et al. (2013) is shown as a black line. The blue and red dashed-dotted lines represent the circumgalactic medium, as fit by Steidel et al. (2011) and Momose et al. (2014) at z ≃ 2.2, we extrapolated inwards. The blue and red solid lines represent the I(r) fit on scales of 10−20 kpc derived from Fig. 9 of Steidel et al. (2011) and Fig. 3 of Momose et al. (2014). Middle: luminosity per kpc² for our PSF-convolved LARS-LAE stack in Lyα (cyan line), for the ground-based PSF profile from Feldmeier et al. (2013, black line), for the 10−20-kpc-scale fit from Steidel et al. (2011, blue line) and Momose et al. (2014, red line). Right: Lyα surface brightness of the z ≃ 5.7 LARS-LAE and LARSaverage stacks before convolving with ground-based PSF (cyan circles and blue triangles) together with that of the PSF-convolved LARS-LAE stack (cyan line). The red dashed-dotted line represents the circumgalactic medium fit by Momose et al. (2014) at z ≃ 5.7, we extended inwards. The red line shows the fit on scales of 5−15 kpc derived from Fig. 3 of Momose et al. (2014).