Search for a Long Living Giant System in $^{238}$U+$^{238}$U Collisions near the Coulomb Barrier

We searched for a long-living component in the collision of 238U+238U between 6.09 A and 7.35 A MeV. The experiment was performed at GANIL using the spectrometer VAMOS, tuned for observing reactions with kinematics similar to quasi-fission events. Theoretical calculations indicate that reactions with strong energy dissipation and a large number of transferred nucleons are correlated to a time delay in the decay of the giant system. We detected events of such type in the focal plane of VAMOS. These events present an excitation function increasing with bombarding energy.