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Effective Nucleon Masses in Symmetric and Asymmetric Nuclear Matter

E. N. E. van Dalen·C. Fuchs·Amand Faessler
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Abstract

The momentum and isospin dependence of the in-medium nucleon mass are studied. Two definitions of the effective mass, i.e. the Dirac mass $m^*_D$ and the nonrelativistic mass $m^*_{NR}$ which parameterizes the energy spectrum, are compared. Both masses are determined from relativistic Dirac-Brueckner-Hartree-Fock calculations. The nonrelativistic mass shows a distinct peak around the Fermi momentum. The proton-neutron mass splitting in isospin asymmetric matter is $m^*_{D,n} m^*_{NR,p}$, which is consistent with nonrelativistic approaches.

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E. N. E. van Dalen, C. Fuchs, Amand Faessler. 2005-05-27. Effective Nucleon Masses in Symmetric and Asymmetric Nuclear Matter. https://doi.org/10.1103/physrevlett.95.022302

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