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H. Stein

Publications and source records attributed to H. Stein.

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Three-dimensional MHD simulation of expanding magnetic flux ropes

Three-dimensional, time-dependent numerical simulations of the dynamics of magnetic flux ropes are presented. The simulations are targeted towards an experiment previously conducted at CalTech (Bellan, P. M. and J. F. Hansen, Phys. Plasmas, 5, 1991 (1998)) which aimed at simulating Solar prominence eruptions in the laboratory. The plasma dynamics is described by ideal MHD using different models for the evolution of the mass density. Key features of the reported experimental observations like pinching of the current loop, its expansion and distortion into helical shape are reproduced in the numerical simulations. Details of the final structure depend on the choice of a specific model for the mass density.

physics.plasm-ph

Medium modification of two-particle scattering in nonideal Bose systems

Medium modification of scattering properties in interacting Bose systems are considered by solving the Bethe-Salpeter equation. An equation of state for the normal phase (generalized Beth-Uhlenbeck formula) is given using the in-medium phase shifts to include two-particle correlations. Conclusions are drawn for systems of bosonic atoms with repulsive interaction such as sodium $^{23}$Na and rubidium $^{87}$Rb. It is shown that the in-medium scattering length and the absolute value of the in-medium scattering phase shift for low scattering energies increase with density.

physics.atom-ph