Dynamics of a relativistic shell model for extended particles

The relativistic harmonic-oscillator model for extended particles with SO(3,2) internal symmetry is used to compute the elastic form factor of the ground state and the radiative decay rate of the $s=1\mathrm{}\to s=0\mathrm{}$ transition. The interactions considered do not test all possibilities of the model. The results are therefore only illustrations of effects due to the extended structure of the particles. The relativistic effects suppress the decay into final states with masses less than 17% of the initial mass, whereas the nonrelativistic decay rate is constant in this region. A representation of the excited states of the model by Hermite polynomials is given.