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Annihilation Mechanism of Dilepton Emission from Finite Fireball

D. Anchishkin·V. Khryapa·R. Naryshkin·V. Ruuskanen
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Abstract

Medium-induced modifications of the pion and quark-antiquark annihilation mechanisms of dilepton production during relativistic heavy ion collisions are considered. Due to the dense hadron environment, the pions produced during a collision are effectively confined in a finite volume, in which they live for a finite time which is scaled as the lifetime of a fireball. Our results indicate that, due to the space-time finiteness of the pion system which generates the corresponding quantum randomization, the dilepton rates are finite in the invariant low-mass region M<2m_π. It is found that the spatial finiteness of quark wave functions and the finiteness of the lifetime of excited states result in the same effect for the quark-antiquark annihilation to dileptons. The breaking of the detailed energy-momentum conservation due to the broken translation invariance is discussed.

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D. Anchishkin, V. Khryapa, R. Naryshkin, V. Ruuskanen. 2004-07-16. Annihilation Mechanism of Dilepton Emission from Finite Fireball. https://arxiv.org/abs/nucl-th/0407042

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