اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurements of the parameters of the $phi(1020)$ resonance through studies of the processes $e^+e^- to K^+K^-$, $K_SK_L$ and $pi^+pi^-pi^0$
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The cross sections of the processes $e^+e^- to K^+K^-$, $e^+e^- to K_SK_L$ and $e^+e^- to pi^+pi^-pi^0$ were measured in the SND experiment at the VEPP-2M collider in the energy region near the $phi(1020)$ meson. These measurements were based on about $10^6$ $K^+K^-$, $0.5 times 10^6$ $K_SK_L$ and $0.4 times 10^6$ $pi^+pi^-pi^0$ selected events. Themeasured cross sections have been analyzed in the framework of the vector meson dominance model and the main parameters of the $phi$-resonance were obtained, such as its mass, width, the production cross section and branching ratios of the main decay modes. The measured value of the $phi$ meson total width, $Gamma_{phi} = 4.21 pm 0.04$ is lower than the present world average of $4.458 pm 0.032$ MeV. Contributions in addition to the conventional vector meson dominance model were found in the $e^+e^- to pi^+pi^-pi^0$ reaction cross section.
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