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Higher excitations of $ω$ and $ϕ$ in dilepton spectra

Kevin Haglin·Charles Gale
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Abstract

We consider lepton pair production via two-hadron annihilation through various isoscalar vector mesons within hot, baryon-free matter. This is tantamount to constructing effective form factors which we model using a vector-meson-dominance approach and compare with experiment. In particular, we consider the reactions $πρ\to e^+e^-$ and $\bar K K^{*}(892)$ + c.c. $\to e^+e^-$. We find that $ω(1390)$ and $ϕ(1680)$ are visible in the mass spectrum for the thermal production rate above the $π^{+}π^{-} \to e^+e^-$ tail and even above the $πa_{1}\to e^+e^-$ results---both of which were considered important in their respective mass regions.

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Kevin Haglin, Charles Gale. 1995-09-05. Higher excitations of $ω$ and $ϕ$ in dilepton spectra. https://doi.org/10.1103/physrevd.52.6297

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