Summary
The reactions π−p→ n+(X0→total) and π−p→ n+(X0→neutrals) have been studied at 1.6 GeV/c with the Bologna-CERN neutron missing-mass spectrometer. Both reactions have been detected without the use of visual techniques. The results are: σ(X0→total)=(108±14) μb and σ(X0→neutrals)=(20.0±3.5) μb, giving a branching ratio Γ(X0→neutrals)/Γ(X0→total)=(18.5±2.2)%. The branching ratio for other possible, so far undetected, neutral decay modes of the X0 turns out to be (2.4±1.9)%.
Riassunto
Studiando le reazioni π−p→ n+(X0→total) e π−p→ n+(X0→neutrals) , con lo spettrometro a neutroni Bologna-CERN, sono state misurate le sezioni d'urto σ(X0→totale) e σ(X0→neutri) e il Branching Ratio Γ(X0→neutri)/Γ(X0→totale)=(18.5±2.2). (noltre il Branching Ratio per possibili decadimenti neutri del mesone X0, finora non rivelati, risulta essere (2.4±1.9)%.
Резюме
Были исследованы реакции π−p→ n+(X0→total) и π−p→ n+(X0→neutrals) при импулбсе 1.6ГэВ/с, с помощью нейтронного спектрометра недостающей массы «Болонья-ЦЕРН». Обе реакции детектировались без использования визуальной техники. Получены следующие результаты: σ(X0→полный)=(108±14) мб и σ(X0→нейтральные)=(20.0±3.5) мб, что приводит к отношению ветвей распадов, равному Γ(X0→нейтральные)/Γ(X0→ полный)=(18.5±2.2)%.
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Basile, M., Bollini, D., Dalpiaz, P. et al. Measurement of the X0 cross-section in π−p interactions at 1.6 GeV/c and determination of the branching ratio (X0→neutrals)/(X0→total). Nuov Cim A 3, 371–384 (1971). https://doi.org/10.1007/BF02813698
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DOI: https://doi.org/10.1007/BF02813698