Riemann sheets barriers

Figure 2.11 3D plot of the Riemann sheet structure of the perturbed Coulomb potential as displayed in Eq (64) with a varying barrier height parameter The imaginary part of Vmax grows toward the viewer. 

Fig. 5.1b. Qualitative behavior of —Q2(rf) for m / 0 in the sub-barrier case. The wavy lines are cuts, and Al and Ak are closed contours of integration. The part of Al that lies on the second Riemann sheet is drawn as a broken line. The phases of Q1 2(r ) indicated in the figure refer to the first Riemann sheet.

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