Figure 7.

(a,b) Comparison of the CIS spectra for the monolayer (dots) and bilayer graphene (lines): (a) p polarization, (b) s polarization. The bilayer curves are a sum of the ${\pi }_{\mathrm{L}}^{*}$ and ${\pi }_{\mathrm{U}}^{*}$ spectra, see Figure 2b for notation. (c,d) Comparison of the monolayer (dots) and hybrid-model (lines) CIS spectra: (c) p polarization, (d) s polarization. The monolayer curves in graphs (a,c) and (b,d) are the same as the curves of the respective colors in Figure 4b. (e,f,g,h) Contrast between the $B_2$ and $A_2$ branches by the hybrid model. Crystal-momentum dependence of the intensity from the $\pi$ and ${\pi }^{*}$ states of the $B_2$ (red) and $A_2$ (black) branch for four photon energies: (e,f) $\hslash \omega =34$ eV (lines) and 35 eV (dots); (g,h) $\hslash \omega =51$ eV (lines) and 52 eV (dots) for p polarization (e,g) and s polarization (f,h).