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Rho Meson Broadening in Hot and Dense Hadronic Matter

Song Gao·Charles Gale·Christoph Ernst·Horst Stöcker·Walter Greiner
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Abstract

The modification of the width of rho mesons due to in-medium decays and collisions is evaluated. The decay width is calculated from the imaginary part of the one-loop self-energy at finite temperature. The collision width is related to the cross sections of the $ρ$ + pion and the $ρ$ + nucleon reactions. A calculation based on an effective Lagrangian shows the importance of including the direct $ρπ\toρπ$ scattering which is dominated by the $a_1$ exchange. A large broadening of the spectral function is found, accompanied by a strength suppression at the pole.

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Song Gao, Charles Gale, Christoph Ernst, Horst Stöcker, Walter Greiner. 1999-06-21. Rho Meson Broadening in Hot and Dense Hadronic Matter. https://arxiv.org/abs/nucl-th/9812059

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