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Probing meson spectral functions with double differential dilepton spectra in heavy-ion collisions

B. Kampfer·O. P. Pavlenko
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Abstract

The double differential dilepton spectrum $dN/ (dM_\perp^2 dM^2)$ at fixed transverse mass $M_\perp$ allows a direct access to the vector meson spectral functions. Within a fireball model the sensitivity of $dN/ (dM_\perp^2 dM^2)$ against variations of both the in-medium properties of mesons and the dynamics of the fireball is investigated. In contrast to the integrated invariant-mass spectrum $dN/dM^2$, in the spectrum $dN/dM^2 dM_\perp^2$ with fixed $M_\perp$ the $ω$ signal is clearly seen as bump riding on the $ρ$ background even in case of strong in-medium modifications.

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B. Kampfer, O. P. Pavlenko. 2000-11-07. Probing meson spectral functions with double differential dilepton spectra in heavy-ion collisions. https://doi.org/10.1007/s100500170149

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