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Medium modification of two-particle scattering in nonideal Bose systems

H. Stein·K. Morawetz·G. Röpke
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Abstract

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.

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H. Stein, K. Morawetz, G. Röpke. 1998-02-27. Medium modification of two-particle scattering in nonideal Bose systems. https://doi.org/10.1103/physreva.55.1945

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