We study the scattering of low-energy tensor multiplet particles against a
BPS saturated cosmic string. We show that the corresponding S-matrix is largely
determined by symmetry considerations. We then apply a specific supersymmetric
model of (2,0) theory and calculate the scattering amplitudes to lowest
non-trivial order in perturbation theory. Our results are valid as long as the
energy of the incoming particle is much lower than the square root of the
string tension. The calculation involves the quantization of a (2,0) tensor
multiplet and the derivation of an effective action describing the low-energy
particles in the presence of a nearly BPS saturated string.Comment: Reference added, typos correcte