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Pion electromagnetic form factor at finite temperature

Chungsik Song·Volker Koch
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Abstract

Temperature effects on the electromagnetic couplings of pions in hot hadronic matter are studied with an effective chiral Lagrangian. We show that the Ward-Takahashi identity is satisfied at non-zero temperature in the soft pion limit. The in-medium electromagnetic form factor of the pion is obtained in the time-like region and shown to be reduced in magnitude, especially near the vector-meson resonance region. Finally, we discuss the consequences of this medium effect on dilepton production from hot hadronic matter.

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Chungsik Song, Volker Koch. 1996-08-07. Pion electromagnetic form factor at finite temperature. https://doi.org/10.1103/physrevc.54.3218

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