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arXiv · 1911.10772

Neutron pairing with medium polarization beyond the Landau approximation

M. Urban·S. Ramanan
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Abstract

We revisit the long-standing problem of the superfluid transition temperature $T_c$ in dilute neutron matter. It is well known that $T_c$ is strongly affected by medium polarization effects (screening) which modify the pairing interaction in the medium. We study these effects within the random-phase approximation (RPA). It turns out that the widely used Landau approximation is sufficient only at densities below about 0.002 fm$^{-3}$. At higher densities, the full RPA leads to stronger screening than the Landau approximation.

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M. Urban, S. Ramanan. 2019-11-25. Neutron pairing with medium polarization beyond the Landau approximation. https://doi.org/10.1103/physrevc.101.035803

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