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arXiv · nucl-th/9903070

Semiclassical transport of particles with dynamical spectral functions

W. Cassing·S. Juchem
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Abstract

The conventional transport of particles in the on-shell quasiparticle limit is extended to particles of finite life time by means of a spectral function A(X,\vec{P},M^2) for a particle moving in an area of complex self-energy Σ^{ret}_X = Re Σ^{ret}_X -i Γ_X/2. Starting from the Kadanoff-Baym equations we derive in first order gradient expansion equations of motion for testparticles with respect to their time evolution in \vec{X}, \vec{P} and M^2. The off-shell propagation is demonstrated for a couple of model cases that simulate hadron-nucleus collisions. In case of nucleus-nucleus collisions the imaginary part of the hadron self-energy Γ_X is determined by the local space-time dependent collision rate dynamically. A first application is presented for A + A reactions up to 95 A MeV, where the effects from the off-shell propagation of nucleons are discussed with respect to high energy proton spectra, high energy photon production as well as kaon yields in comparison to the available data from GANIL.

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W. Cassing, S. Juchem. 1999-09-22. Semiclassical transport of particles with dynamical spectral functions. https://doi.org/10.1016/s0375-9474(99)00393-0

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