The problem with beta decay The prehistory of the neutrino starts in 1896 when Henri Becquerel discovered some strange radiation emitted by uranium salts [Bec96]. Isolating the radium, Pierre and Marie Curie named this new phenomenon “radioactivity”. Ernest Rutherford showed that Continue Reading …
Discovering the radioactivity In 1896, Henri Becquerel discovered some strange radiation coming from uranium salts [Bec96]. Two years later, Pierre and Marie Curie isolated radium, a material far more radioactive than uranium and Marie Curie called this spontaneous emission of Continue Reading …
In spite of the prediction by Bethe and Peierls [Bet34], several physicists attempted to see the neutrino, among them Nahmias, Crane, Allen [Nah35,Cra38,All42]. Until the end of the 1940’s, they tried to measure the recoil of a nucleus during its Continue Reading …
The muon-neutrino : The neutrino (or more exactly the anti-neutrino) coming out of a nuclear reactor is an electron-neutrino because, in the beta decay process, it is emitted together with an electron. But another weak interaction process, the decay of Continue Reading …
Neutrino: a fundamental particle of weak interaction Matter is made of atoms, composed of a nucleus (made of protons and neutrons) surrounded by electrons. Protons and neutrons are each made of three elementary particles named “quarks”. Electrons are one type Continue Reading …
The first idea of neutrino masses, mixing and oscillations was suggested by Bruno Pontecorvo in 1957 [Pon57]. He thought that there was an analogy between leptons and hadrons and that neutrinos could oscillate in an analogous way to the K0-antiK0 Continue Reading …
A lot of progress has been made in our understanding of the neutrinos over the last 30 years, since the discovery of neutrino oscillation by the SuperKamiokande experiment. Among the pending questions, we can list: Is there a 4th neutrino Continue Reading …
Neutrinos are, with the photons, the most abundant particles in the Universe. In the big bang theory (the “standard” model of the Universe), light neutrinos have thermally decoupled from the other forms of matter (quarks and leptons) approximately 1 second Continue Reading …
Since the pioneering work of Bethe and others, it was anticipated that the energy of the Sun was produced in its core by the fusion of hydrogen into helium [Wei37,Bet38,Bet39]. This process is accompanied by the emission of neutrinos, which Continue Reading …
Cosmic rays (protons or nuclei) interact in the upper atmosphere of the Earth. The resulting pions and kaons decay into muons and muon-neutrinos, many of the muons then decay into electrons and a muon-neutrino electron-neutrino pair. All these neutrinos are Continue Reading …
