The L3 detector at LEP has been used to determine the number of light neutrino families by measuring the cross section of single photon even in e+e- collisions at energies near the Z0 resonance. We have observed 61 single photon candidates with more than 1.5 GeV of deposited energy in the barrel electromagnetic calorimeter, for a total integrated luminosity of 3.0 pb-1. From a likelihood fit to the single photon cross sections, we determine N(nu) = 3.24 +/- 0.46 (statistical) +/- 0.22 (systematic).
A Direct Determination of the Number of Light Neutrino Families From E+e--]nu-nu-bar-gamma At Lep
SANTOCCHIA, Attilio;FIANDRINI, Emanuele;PAULUZZI, Michele
1992
Abstract
The L3 detector at LEP has been used to determine the number of light neutrino families by measuring the cross section of single photon even in e+e- collisions at energies near the Z0 resonance. We have observed 61 single photon candidates with more than 1.5 GeV of deposited energy in the barrel electromagnetic calorimeter, for a total integrated luminosity of 3.0 pb-1. From a likelihood fit to the single photon cross sections, we determine N(nu) = 3.24 +/- 0.46 (statistical) +/- 0.22 (systematic).File in questo prodotto:
Non ci sono file associati a questo prodotto.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
