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P-Wave Polarization of the $ρ$-Meson and the Dilepton Spectrum in Dense Matter

Bengt Friman·H. J. Pirner
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Abstract

We study the $p$-wave polarization operator of the $ρ$-meson due to $ρN$ interactions via the $N^*$ (1720) and $Δ(1905)$ resonances and compute the corresponding production rate for $e^+e^-$-pairs at finite temperature and baryon density. At high baryon density we find a significant shift of the spectrum to lower invariant masses.

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Bengt Friman, H. J. Pirner. 1997-01-08. P-Wave Polarization of the $ρ$-Meson and the Dilepton Spectrum in Dense Matter. https://doi.org/10.1016/s0375-9474(97)00050-x

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