The nuclear response-of Xe-136 and Pb-208 to electromagnetic excitatio
n was studied in peripheral, near-relativistic heavy-ion collisions. L
arge cross sections were observed for the one-phonon and two-phonon is
ovector giant dipole resonance. The results, in particular the unexpec
tedly large strength found for the double giant dipole resonance, are
discussed and compared to that of other recent measurements.