Single-potential barrier penetration

Figure 19 Diagram for single-potential barrier penetration and reflection.

The Coulomb barrier is generally of the order of 1 MeV even in the case of interaction of singly charged particles with the lightest nuclei. Since the quantum mechanics provides with the finite probability for interaction, the under-barrier reactions (for impinging particles with energy below the potential barrier) are still possible. However, the penetrability of the Coulomb barrier increases very rapidly as Ei approaches Be ... 

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