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Probing the strange quark condensate by di-electrons from phi meson decays in heavy-ion collisions at SIS energies

B. Kampfer·O. P. Pavlenko·S. Zschocke
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Abstract

QCD sum rules predict that the change of the strange quark condensate $<\bar s s>$ in hadron matter at finite baryon density causes a shift of the peak position of the di-electron spectra from $ϕ$ meson decays. Due to the expansion of hadron matter in heavy-ion collisions, the $ϕ$ peak suffers a smearing governed by the interval of density in the expanding fireball, which appears as effective broadening of the di-electron spectrum in the $ϕ$ region. The emerging broadening is sensitive to the in-medium change of $<\bar s s>$. This allows to probe directly in-medium modifications of $<\bar s s>$ via di-electron spectra in heavy-ion collisions at SIS energies with HADES.

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B. Kampfer, O. P. Pavlenko, S. Zschocke. 2002-11-22. Probing the strange quark condensate by di-electrons from phi meson decays in heavy-ion collisions at SIS energies. https://doi.org/10.1140/epja%2Fi2002-10146-1

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