Catálogo de publicaciones - libros

The decays predominantly into an electron, a muon neutrino and an electron anti-neutrino: This is a process of great phenomenological importance, since the measurement of the muon lifetime provides the most precise determination of the Fermi constant , and one of the most precise measurements in the whole field of elementary particle physics. In this Section, we describe the calculation of the corresponding decay rate in some detail.

In the original formulation of the standard model, presented in Chapters 7, 8 and 9, neutrinos are massless particles. This feature is well motivated by direct experimental upper bounds on neutrino masses: and even if observations indicate that neutrino masses are in fact non-zero, the approximation ≪ , where is any fermion in the standard model spectrum, is extremely good for most applications. In view of experimental results, however, it is interesting to study the possible ways neutrino mass terms can be consistently introduced.