Neutrino Mass example essay topic

The first real evidence that neutrinos may posses tiny particles of mass where when a giant particle detector was located deep in a mind in Japan. Neutrinos carry no electric charge. This particle-detecting equipment is sensitive only to charted particles, scientists are not able to observe neutrinos directly. If a neutrinos collides with a proton or neutron, the particles in the nucleus of and atom, the neutrino is transformed into a charged particle. There are three kinds of neutrinos. Electron neutrinos became electrons.

The other two types are mu-neutrinos and tau-neutrinos, which transform into particles called muons and taus. The neutrinos studied in Japan originated high in the Earth's atmosphere. They were produced from reactions induced by high-energy comic-ray particles colliding with air molecules. Physicists created sophisticated instruments, such as Japan's Super-Kamiokande, or Super-K detector. The primary feature of the Super = K is a tank containing 45 million liters of ultrapure water. Another important feature is that it is located about 1.000 meters underground.

By building the detector so far underground, the researchers could screen out almost all other particles and therefore observe almost exclusively the reactions of the neutrinos. The neutrino can't simply disappear, it must be transformed into another particle. Tau-neutrinos are difficult to detect because they very rarely have enough energy when colliding with a proton or neutron to transform into the heave tau particle. Physicists know that in order for the oscillation process to take place, one or both of the neutrinos must have mass, and their masses must be different. The bigger the difference in masses, the faster the oscillation. Particles masses are measured in units of energy.

These units are called electro volts. The researchers could not measure the masses of the neutrinos, but they could measure the rate of oscillation and then use a mathematical formula and predictions based on their other particle research to make a rough estimate of the neutrino mass. Neutrinos are millions times lighter than an electron. The nuclear reactions that power the sun should produce a steady and predictable stream of e-neutrinos. But detectors on Earth observe only 30-60 percent of the number predicted. This could be the result of e-neutrinos oscillating to one or both the other two types of neutrinos on their way to Earth.

The so-called dark matter is where the Super-K might have shed some light. There have been many suggestions as to what the invisible dark matter might be. Neutrinos with mass might be a part of the answer. A number of experiments capable of revealing more about neutrino masses were in preparation in 1999.