Latest documents http://publikationen.stub.uni-frankfurt.de/index/index/ Fri, 30 Jun 2006 11:16:27 +0200 Fri, 30 Jun 2006 11:16:27 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/2479 We calculate the spin polarization of 1sσ vacancies and emitted δ electrons induced by the strong magnetic field (|Bmax|∼1016G) in collisions of very heavy ions (Z1+Z2=178). The electron excitations are determined by the solution of coupled-channel equations within the quasimolecular basis states including the vector potential. The formulation is extended to the many-electron case. Spin polarizations of the order of 5-10% for impact energies below the Coulomb barrier are predicted. Gerhard Soff; Joachim Reinhardt; Walter Greiner article http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/2479 Fri, 30 Jun 2006 11:16:27 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/2496 This paper reports calculations of the influence of a reaction time T>10-21 s in deep-inelastic Xe-Pb collisions on the energy spectrum of δ electrons ejected in the same collision. It is shown that the lifetime of the superheavy composite system causes pronounced oscillations of width ε=h/T in the electron distribution, which survive the inclusion of multistep excitations and the folding with a lifetime distribution function. This effect may serve as an atomic clock for deep-inelastic collisions. Gerhard Soff; Joachim Reinhardt; Berndt Müller; Walter Greiner article http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/2496 Wed, 28 Jun 2006 11:57:22 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/2509 The theory of direct electron-positron pair production in the collision of heavy ions is formulated in the framework of the quasimolecular model. The pair production process acquires a collective nature for (Z1+Z2)α>1 and can be understood as the shakeoff of the strong vacuum polarization cloud formed in the quasimolecule. The total cross section is, e.g., 76 μb for Pb + Pb at Coulomb barrier energies. Gerhard Soff; Joachim Reinhardt; Berndt Müller; Walter Greiner article http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/2509 Wed, 28 Jun 2006 10:20:10 +0200