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The reaction $Δ+N\to N+N+ϕ$ in ion-ion collisions

Michail P. Rekalo·Egle Tomasi-Gustafsson
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Abstract

We study the threshold $ϕ$-meson production in the process $Δ+N\to N+N+ϕ$, which appears as a possible important mechanism in high energy nuclei-nuclei collisions. The isotopic invariance of the strong interaction and the selection rules due to P-parity and total angular momentum result in a general and model independent parametrization of the spin structure of the matrix element in terms of three partial amplitudes. In the framework of one-pion exchange model these amplitudes can be derived in terms of the two threshold partial amplitudes for the process $π+N\to N+ϕ$. We predict the ratio of cross sections for $ϕ-$meson production in $pp$- and $ΔN$-collisions and the polarization properties of the $ϕ$-meson, in $Δ+N\to N+N+ϕ$, as a function of a single parameter, which characterizes the relative role of transversal and longitudinal $ϕ$-meson polarizations in the process $π+N\to N+ϕ$.

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Michail P. Rekalo, Egle Tomasi-Gustafsson. 2002-05-06. The reaction $Δ+N\to N+N+ϕ$ in ion-ion collisions. https://doi.org/10.1103/physrevc.67.044004

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