Hola! I am Alexa Guido, a young curious woman who loves science. Come and discover some of the curiosities of this universe through the eyes of physics.
The ghostly particle, the second most abundant particle in the universe only after light, is almost massless and extremely hard to trace, this is a brief introduction to the neutrino. Neutrinos are electrically neutral particles of spin ½, do not participate in strong interactions, and as the name “neutral (neutral) small (ino) particle” implies, neutrinos are very tiny elementary particles; to bring into perspective a 500 ml PET bottle contains about 150,000 neutrinos. Even so, trillions of neutrinos are still passing through your body at nearly the speed of light.
In 1930, W. Pauli was studying the energy of radiation emitted by atomic nuclei, he wondered how he could explain how some energy could disappear. So, he came up with an idea, “there may be a ghost-like particle with no electricity that is ejected somewhere before one knows it.” At the time, Pauli called that particle “neutron,” which is known as a neutrino today. Almost 30 years after that, the American physicists Reines and Cowan succeeded in detecting neutrinos produced in nuclear reactors, and finally neutrinos were discovered for the first time.
Neutrinos were generated when the universe was born. Still, nowadays they are produced when a massive star explodes at the end of its life, when cosmic rays from the universe collide with the earth’s atmosphere and, mostly everything in the universe generates neutrinos, even you and me.
According to the Standard Model, electrons and neutrinos are like relatives with or without electric charges. Corresponding to the types of electrons (electron, muon, and tau), there are three types, also named flavors, of neutrinos: electron neutrino, muon neutrino, and tau neutrino. There are three types of antineutrinos as well.
There is something curious about neutrinos, imagine purchasing a carton of chocolate ice cream at the store, driving home, and opening it only to find it was vanilla! So you put a scoop of vanilla in your bowl and walk into the other room to eat it, where you are surprised to find it is now strawberry. That’s what happens with neutrinos. A particle might start as an electron neutrino, but as it moves, it converts into a muon neutrino or a tau neutrino, changing flavors as it goes.
In contrast with the past, the Super-Kamiokande observes various neutrinos and other particles, this is the biggest neutrino experiment ever constructed, also you can do a virtual tour at the Super-Kamiokande official website. Neutrinos play a very important role in various branches of subatomic physics as well as in astrophysics and cosmology. The smallness of neutrino mass is very likely related to the existence of new, yet unexplored mass scales in particle physics. Furthermore, neutrino reactions play a crucial role in the mechanism of supernova explosions; and there are intricate relationships between neutrino physics and nuclear physics.
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