A proton beam-dump experiment using the CHARM neutrino detector has been performed at the CERN SPS. We report the observation of events induced by prompt νμ neutrinos and confirm previous evidence for prompt electron neutrinos. The ratio of prompt (νe + νe) and (νμ+νμ) fluxes is found to be 0.48+/-0.12 (st atistical) +/- 0.10 (systematic), whereas a flux ratio of 1 is expected for charmed meson production and subsequent semileptonic decay. The νμ to νμ flux ratio obtained is 1.3-0.6+6. We also observe 54 +/- 19 (statistical) +/- 9 (systematic) promp t muonless events, with shower energy in the range from 2 to 20 GeV, in excess of electron and muon neutrino interactions expected from D and D meson decay.
Experimental Study of Prompt Neutrino Production in 400 GeV Proton-Nucleus Collisions
FERRONI, Fernando
1980-01-01
Abstract
A proton beam-dump experiment using the CHARM neutrino detector has been performed at the CERN SPS. We report the observation of events induced by prompt νμ neutrinos and confirm previous evidence for prompt electron neutrinos. The ratio of prompt (νe + νe) and (νμ+νμ) fluxes is found to be 0.48+/-0.12 (st atistical) +/- 0.10 (systematic), whereas a flux ratio of 1 is expected for charmed meson production and subsequent semileptonic decay. The νμ to νμ flux ratio obtained is 1.3-0.6+6. We also observe 54 +/- 19 (statistical) +/- 9 (systematic) promp t muonless events, with shower energy in the range from 2 to 20 GeV, in excess of electron and muon neutrino interactions expected from D and D meson decay.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
