Fig. 4. ARPES measurements on Fermi arcs in [Gd₂C]²⁺·2e⁻.

Photon energy-dependent Fermi surfaces (FSs) near the $\overline{\mathrm{K}}$ point (left) and their 2D curvature plots to enhance FS features (right). Both panels are symmetrized with respect to k_x = 0 for better visualization of Fermi arcs. Light red and light blue points indicate W₈⁺ and W₈⁻ WPs, respectively. Black solid lines denote BZ boundaries. Fermi arcs are drawn with dashed line segments connecting W₈ WPs. In the original data for the 90 eV Fermi surface, all Fermi arcs are displayed, but they are omitted in the other plots except one used for comparison.