Showing papers by "Georges Azuelos published in 1986"
TL;DR: In this paper, a search has been carried out for the production of neutrinos in the mass range 60 to 130 MeV coupling to the electron in the decay chain of the π-mu..-e decay chain.
Abstract: A search has been carried out for the production of neutrinos in the mass range 60 to 130 MeV coupling to the electron in the decay ..pi../sup +/..-->..e/sup +/..nu... The dominant background from the ..pi..-..mu..-e decay chain has been suppressed by use of a new technique leading to more than an order of magnitude greater sensitivity than achieved previously.
17 citations
01 Jan 1986
TL;DR: In this paper, it was shown that the standard model does not allow any partial lepton number violation in the electroweak group SU(2) × U(l) with the minimal particle content (no right-handed neutrino, only one Higgs doublet).
Abstract: The question of muon — to — electron conversion is as old as the muon itself. When it was realised that the muon does not decay into electron and photon the concept of separately conserved muonic and electronic lepton numbers was introduced as an ad hoc hypothesis, without profound justification. But it is only recently that this question has become of great importance, with the advent of the gauge theories of fundamental interactions. The “standard model” based on the electroweak group SU(2) × U(l) with the minimal particle content (no right-handed neutrino, only one Higgs doublet) does not allow any muon number (or any partial lepton number) violation. But the “standard model” is not believed to be the final theory of nature. It has to be modified, generalised, and hopefully embedded in a more complete unification scheme. To do this there are many possibilities which lead to muon number violation in a very natural and inescapable way. Therefore the study of muon number (and other lepton number) violation is one of the most important issues in particle physics. Processes which violate muon number have already been searched for extensively at the meson factories. They have not been observed but very stringent upper limits for their existence have been obtained, which put strong constraints on theoretical models, in particular on mixing parameters and masses of hypothetical particles on the TeV scale. All muon number violating processes are important and must be studied. They will be discussed at length by other speakers at this conference.