  Low energy dynamics of magnetic monopoles and anti-monopoles in the U(2)
gauge theory is studied in the Higgs (non-Abelian superconducting) phase. The
monopoles in this superconducting phase are not spherical but are of slender
ellipsoid which are pierced by a vortex string. We investigate scattering of
the slender monopole and anti-monopole, and find that they do not always decay
into radiation, contrary to our naive intuition. They can repel, make bound
states (magnetic mesons) or resonances. Analytical solutions including any
number of monopoles and anti-monopoles are obtained in the first non-trivial
order of rigid-body approximation. We point out that some part of solutions of
slender monopole system in 1+3 dimensions can be mapped exactly onto the
sine-Gordon system in 1+1 dimensions. This observation allows us to visualize
dynamics of monopole and anti-monopole scattering easily.
