Etude et impact du bruit de fond corrélé pour la mesure de l'angle ...

Chapter 2
Neutrino physics
tel-00821629, version 1 - 11 May 2013
In this chapter the physics related to the neutrino is widely discussed both
from the theoretical and experimental point of view, with a particular focus
on neutrino oscillation. The current state of the art regarding the measurement
of the oscillation parameters is given with a description of the most
important experiments in this field. The problem related to the nature of the
neutrino mass is also briefly described. Finally, the open questions and the
future e↵orts to be addressed by the neutrino community are also discussed.
2.1 The standard model of particle physics, an
overview
The Standard Model of particle physics (SM) is the theory describing how
the fundamental constituents of our universe interact.
From the technical point of view the SM is a renormalisable gauge field theory,
based on the symmetry group SU(3) C ⌦SU(2) L ⌦U(1) Y which describe
strong, weak and electromagnetic interaction, via the exchange of spin-1
gauge field: eight massless gluons for the strong interaction, one massless
photon for the electromagnetic interaction and three massive bosons, W ±
and Z 0 for the weak interaction.
The known elementary particles and antiparticles are fermions with spin-1/2
and are organised in two families according on how they interact: quarks
and leptons. Quarks interacts with all the three forces, while leptons interact
only through the electromagnetic and/or the weak force. Quarks
and leptons exist in three generations or flavours, with di↵erent masses and
flavour quantum numbers, but with identical interactions, which make the
SM symmetric with respect to the flavour. A summary of SM fermions
and bosons is shown Fig. 2.1.
The fermions are a representation of the symmetry group and can be written
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