The interaction between nucleons can be written as a potential, but the form of the potential is determined by the dominant physics. The nucleon is a composite particle made of quarks, which suggests the force will be strongly repulsive at short range, nonlocal, and exhibit excitability. To determine which if any property dominates scattering, I fit to scattering data with three distinct potentials, each of which exhibits one property: a local potential with a hard-core, a nonlocal potential, and a two-level potential; I then fit each model with and without one-pion exchange to scattering data using Broyden's method with the reduced __ serving as the fitness function for my method. The hard-core model performs the best, and the nonlocal potential outperforms the two-level model.
