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Critical Enhancement of the In-medium Nucleon-Nucleon Cross Section at low Temperatures

T. Alm·G. Roepke·M. Schmidt
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Abstract

The in-medium nucleon-nucleon cross section is calculated starting from the thermodynamic T-matrix at finite temperatures. The corresponding Bethe-Salpeter-equation is solved using a separable representation of the Paris nucleon-nucleon-potential. The energy-dependent in-medium N-N cross section at a given density shows a strong temperature dependence. Especially at low temperatures and low total momenta, the in-medium cross section is strongly modified by in-medium effects. In particular, with decreasing temperature an enhancement near the Fermi energy is observed. This enhancement can be discussed as a precursor of the superfluid phase transition in nuclear matter.

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T. Alm, G. Roepke, M. Schmidt. 1994-04-12. Critical Enhancement of the In-medium Nucleon-Nucleon Cross Section at low Temperatures. https://doi.org/10.1103/physrevc.50.31

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