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在库仑能垒下的重离子碰撞中，当核接触时，可以形成双核系统（DNS）。这使得核子交换成为可能，而核子交换通常伴随着动能的耗散。在此期间，原子核粘在一起。研究了库仑排斥起主导作用的超重核DNS 238 U +238 U（Z=184）的交换核子数、能量耗散和核接触时间之间的相关性.我们在不同的束流能量下进行了测量，发现转移产物的动能与束流能量无关。这意味着可用的动能被完全耗散，并且转移产物的能量仅由其库仑势垒决定。不同的理论方法预测这些事件的一个子集的异常长的核接触时间超过5×10-21 s。在SHIP中，DNS以180°的步长旋转变得“可见”。这使我们能够确定DNS的旋转时间和核相互作用时间的下限。

In heavy ion collisions at Coulomb barrier energies a di-nuclear system (DNS) can be formed when the cores come into contact. This enables the exchange of nucleons which is usually accompanied by the dissipation of kinetic energy. During this time the nuclei stick together. We investigated the correlation between the number of exchanged nucleons, the energy dissipation and the nuclear contact time with the superheavy DNS 238U + 238U (Z=184) where the Coulomb repulsion plays a dominant role. We performed the measurements at different beam energies and found that the kinetic energy of the transfer products is independent of the beam energy. This means that the available kinetic energy is completely dissipated and the energy of the transfer products is only determined by their Coulomb barrier. Different theoretical approaches predict exceptionally long nuclear contact times of more than 5×10-21 s for a subset of these events.A direct experimental access to these interaction times we expect from experiments at the velocity filter SHIP at GSI. At SHIP the rotation of DNS in steps of 180° becomes "visible". This allows us to determine lower limits for the rotation time of the DNS and nuclear interaction time, respectively.