Neutrino,The Ghost Particle

A neutrino is a sub-atomic particle which is similar to an electron, but there is no electrical charge and very small mass, which can also be zero. Neutrinos is one of the most abundant particles of the universe. Because they have a very little talk with the substance, however, finding them is incredibly difficult. Atomic forces deal with the identification of electrons and neutrons; Neither do participate in strong atomic force, but both of them share equally in the nuclear force. The particle of this property is called Leptin. In addition to electrons (and this is anti-particle, positron), charged leptons include muon (200 times more massive than an electron), tau (3,500 times greater than electrons on a large scale). And their anti-particle.

Like an electron, both neutrinos are mixed in muon and tau, which are called muon-neutrino and tau-neutrino. Three types of neutrinos appear differently: for example, when muon-neutrinos interact with a target, they will always produce a muon, and will never be tossed or electrons. In particle interactions, although electrons and electron-neutrinos can be created and destroyed, the number of electrons and electron-neutrinos is preserved. This fact divides Lepton into three families, each with a charged lepton and its neutrinos.

To detect neutrinos, very large and very sensitive detectors are required. Typically, a low-energy neutrino passes light-years of many common cases before interacting with anything. As a result, all terrestrial neutrino experiments rely on measuring small portions of neutrinos, which interact in proper size detectors. For example, in the Sudbury Neutrino Observatory, a 1000-ton heavily-soluble solar-neutrino detector raises approximately 1012 neutrino. Approximately 30 neutrinos are detected per day.

For the first time, Wolfgang Pauli underlined the presence of neutrinos in 1930. At that time, a problem arose because it seemed that both the energy and angular momentum in beta-decay was not preserved. But Pauli said that if a non-interactive, neutron particle - neutrinos - is emitted, then one can recover the protection laws. The first address of neutrinos did not last until 1955 when Clyde Cowan and Friedrich Reynings recorded anti-neutrinos emitted by a nuclear reactor.

Natural sources of neutrinos include radioactive decay of primordial elements within the Earth, which generate a large flow of low-energy electron-anti-neutrinos. The calculation shows that about 2 percent of the Sun's energy is made by neutrino generated in the fusion reactions. Supernova is also primarily a neutrinos phenomenon because neutrinos are the only particles that can distinguish very dense material from a crumbling star; Only a small fraction of available energy is converted to light. It is possible that a large part of the black body of the universe is composed of primordial, big bang neutrino.


Areas related to neutrinos and astrophysics are growing prosperous, diverse and rapidly. It is therefore impossible to try to explain all the activities briefly in the field. He said the current questions which attract a large amount of experimental and theoretical effort include the following: What are the masses of different neutrinos? How do they affect Big Bang Cosmology? Do neutrinos oscillate? Or a type of neutrino can travel through substance and space and change in another type? Are neutrinos different from its radical particles? How do the stars fall and make supernova? What is the role e of neutrino in cosmology?

Especially a long-term issue of interest is the so-called solar neutrino problem. This name refers to the fact that many terrestrial experiments spread over the last three decades have consistently seen that less energy is needed than solar neutrinos to produce energy released from the sun. One possible solution is that the neutrinos oscillate - that is, the electrons produced in the sun are converted into muon or tau-neutrino, as well as neutrinos going to the Earth. Because low-energy muon- or tau-neutrino is more difficult to measure, this kind of transformation will explain why we have not seen the exact number of neutrino on the Earth.