A direct determination of the number of light neutrino families from e<SUP>+</SUP> e<SUP>-</SUP> → vvγ at LEP

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 Z° resonance. We have observed 61 single photon candidates with more than 1.5 GeV of deposited energy in the barrel el...

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Detalles Bibliográficos
Autores principales: Dova, María Teresa, L3 Collaboration
Formato: Articulo
Lenguaje:Inglés
Publicado: 1992
Materias:
LEP
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/74004
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Descripción
Sumario: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 Z° 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 Nv = 3.24 ± 0.46 (statistical) _+ 0.22 (systematic).