We have achieved overall energy resolution of the order of 12 meV. We used FeSuMa, laser radiation of 6 eV, single crystals of LiFeAs and carried out experiments at 3K. The EDC shown in the middle panel of the lower row is a background EDC from the momentum location shortly after k_F (~110 from the left panel) when all sharp peaks are gone and spectrum looks like a Fermi edge. It is integrated within 10×10 pixels of the camera from the 500×500 dataset (upper row, in the middle). There are 34 layers in this 3D wave – the energy steps taken every 2 meV. Each layer took 20 seconds.
