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The Delta-Hole model at Finite Temperature

P. A. Henning·H. Umezawa
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Abstract

The spectral function of pions interacting with a gas of nucleons and Delta-33-resonances is investigated using the formalism of Thermo Field Dynamics. After a discussion of the zero Delta-width approximation at finite temperature, we take into account a constant width of the resonance. Apart from a full numerical calculation, we give analytical approximations to the pionic spectral function including such a width. They are found to be different from previous approximations, and require an increase of the effective Delta-width in hot compressed nuclear matter. The results are summarized in an effective dispersion relation for interacting pions.

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P. A. Henning, H. Umezawa. 1993-04-08. The Delta-Hole model at Finite Temperature. https://doi.org/10.1016/0375-9474(94)90713-7

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