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Short-Lived Phi Mesons

Laura Holt·Kevin Haglin
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Abstract

We use effective hadronic field theory to study in-medium properties of the $ϕ$ meson. The dominant decay channels $ϕ\toK^{+}K^{-}$ and $ϕ\toπρ$ are modeled using an SU(3) chiral Lagrangian with normal and abnormal parities. The $ϕ$ self-energy is approximated to one-, two-, and even three-loop order in the strong coupling. Effects of modified spectral functions for $π$, $K$, $ρ$ and $ϕ$ are also included in the calculation. This allows us to study in-medium decay of phi mesons into (in-medium) kaon-pair daughters and (in-medium) $πρ$ pairs. The results point to the possibility of rather short-lived $ϕ$'s, short enough to decay inside the fireball in relativistic heavy ion collisions. Implications relevant for the NA49 and NA50 experimental results, recently dubbed the ``$ϕ$ puzzle'', are discussed.

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Laura Holt, Kevin Haglin. 2004-09-17. Short-Lived Phi Mesons. https://doi.org/10.1088/0954-3899%2F31%2F4%2F030

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