Study ofωExchange Isolated in the Reactionsπp→ρNat 6GeVc

Abstract

Dips are observed at $t\sim -0.45\mathrm{}$ Ge${\mathrm{V}}^2$ in the differential cross sections of the reactions ${\pi }^{\pm }p\to {\rho }^{\pm }p$ and a break at $t\sim -0.25\mathrm{}$ Ge${\mathrm{V}}^2$ in ${\pi }^{-}p\to {\rho }^{0}n$ at 6 $\frac{\mathrm{GeV}}{c}$. The $I=0\mathrm{}$ $\omega$-exchange contribution in the $t$ channel is isolated by calculating $R^2\mathrm{}\left(t\right)=\frac{1}{2}\left[\frac{d\sigma }{\mathrm{dt}}({\pi }^{-}p\to {\rho }^{-}p)+\frac{d\sigma }{\mathrm{dt}}({\pi }^{+}p\to {\rho }^{+}p)-\frac{d\sigma }{\mathrm{dt}}({\pi }^{-}p\to {\rho }^{0}n)\right].$ The function $R^2\mathrm{}\left(t\right)\mathrm{}$ vanishes at $t\sim -0.45\mathrm{}$ Ge${\mathrm{V}}^2$ and is well parametrized by a Bessel function of the first kind, ${J_1}^2\left(r\sqrt{-t}\right)$, with $r\sim 1$ F.