Dark matter: Heavy neutrinos

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Description

This lecture explores the seesaw mechanism, an unconfirmed hypothesis aiming to prove experimentally that neutrinos are Majorana particles. It discusses the Majorana mass term, the physical masses obtained after matrix diagonalization, and the implications of heavy neutrinos in the standard model of particle physics.

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https://mediaspace.epfl.ch/media/0_r3lm0ehr

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Neutrino oscillation is a quantum mechanical phenomenon in which a neutrino created with a specific lepton family number ("lepton flavor": electron, muon, or tau) can later be measured to have a different lepton family number. The probability of measuring a particular flavor for a neutrino varies between three known states, as it propagates through space. First predicted by Bruno Pontecorvo in 1957, neutrino oscillation has since been observed by a multitude of experiments in several different contexts.

Experimental physics

Experimental physics is the category of disciplines and sub-disciplines in the field of physics that are concerned with the observation of physical phenomena and experiments. Methods vary from discipline to discipline, from simple experiments and observations, such as Galileo's experiments, to more complicated ones, such as the Large Hadron Collider. Experimental physics is a branch of physics that is concerned with data acquisition, data-acquisition methods, and the detailed conceptualization (beyond simple thought experiments) and realization of laboratory experiments.

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