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The $σ$ meson in a nuclear medium through two pion photoproduction

L. Roca·E. Oset·M. J. Vicente Vacas
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Abstract

We present theoretical results for $(γ, π^0 π^0)$ production on nucleons and nuclei in the kinematical region where the scalar isoscalar $ππ$ amplitude is influenced by the $σ$ pole. The final state interaction of the pions modified by the nuclear medium produces a spectacular shift of strength of the two pion invariant mass distribution induced by the moving of the $σ$ pole to lower masses and widths as the nuclear density increases.

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L. Roca, E. Oset, M. J. Vicente Vacas. 2002-08-23. The $σ$ meson in a nuclear medium through two pion photoproduction. https://doi.org/10.1016/s0370-2693(02)02188-3

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