• MEG II
• CLFV
• violazione del sapore leptonico
• SiPM
• fotomoltiplicatori al silicio
• beam monitor

In this thesis I present the design, simulation and test of two new fast beam monitoring tools based on plastic scintillators coupled to SiPMs in the context of the MEGII experiment, which aims to detect the µ+ → e+ γ decay. They are a scintillating fibers detector(SciFi), designed to work in vacuum, and a matrix of scintillating elements (MatriX). Both of them are able to perform particle ID, to measure beam characteristics with high precision in a few seconds and to work in a high magnetic field.
Another part of my work consisted in simulating the new LH2 target used to calibrate the LXe calorimeter used in the MEGII experiment through the Charge Exchange reaction: p(π − , π 0 )n. This method uses the two γ coming from π 0 decay, uniformly distributed in energy between 54.9 and 82.9 MeV, to calibrate the detector near the signal region.