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arXiv · hep-ph/9809419

Towards a Quantum Transport Description of Particles with finite Mass Width

J. Knoll·Yu. B. Ivanov·D. N. Voskresensky
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Abstract

The effects of the propagation of particles which have a finite life time and an according width in their mass spectrum are discussed in the context of transport descriptions. In the first part the coupling of soft photon modes to a source of charged particles is studied in a classical model which can be solved completely in analytical terms. The solution corresponds to a re-summation of certain field theory diagrams. The second part addresses the derivation of transport equations which also account for the damping width of the particles. The $Φ$-derivable method of Baym is used to derive a self-consistent and conserving scheme. For this scheme a conserved energy-momentum tensor can be constructed. Furthermore, a kinetic entropy can be derived which besides the standard quasi-particle part also includes contributions from fluctuation.

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J. Knoll, Yu. B. Ivanov, D. N. Voskresensky. 1998-11-27. Towards a Quantum Transport Description of Particles with finite Mass Width. https://arxiv.org/abs/hep-ph/9809419

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