  In this note we study the conversion of nucleons into deltas induced by a
strong magnetic field in ultraperipheral relativistic heavy ion collisions. The
interaction Hamiltonian couples the magnetic field to the spin operator, which,
acting on the spin part of the wave function, converts a spin 1/2 into a spin
3/2 state. We estimate this transition probability and calculate the cross
section for delta production. This process can in principle be measured, since
the delta moves close to the beam and decays almost exclusively into pions.
Forward pions may be detected by forward calorimeters.
