Neutrinos detected for the first time

neutrinos detected

Scientists have for the first time detected the neutrino particles, formed by the fusion of two protons in the sun, in the Borexino detector here on earth .

Neutrinos a weird particle probably best known for being “accused” of traveling faster than light which was later disproved as a mathematical error. Neutrinos are similar to electrons but do not have an electric charge something that is very helpful if you want to avoid interacting with almost everything in the universe. The lack of charge and very slim mass makes the neutrino able to travel long distances and can pass through regular matter pretty easily. In a cute side note neutrino means “little neutral one” in Italian.


Proton-Proton Neutrinos Detected

In the experiment the scientists had to come up with a way to detect the neutrino as it hit matter on earth. This is extremely tricky since neutrinos rarely interact with regular matter and unfortunately regular matter is all we have to build detectors with. The researchers solved this issue by building a detector 1.4 kilometers under the surface and surrounding the detector with a 1000 tons of water in a shield around it. The reason for this is to remove all other possible ways of radiation to interacts with the detector except the neutrinos. Since the neutrinos can pass right through most matter and since approximately 65 billion neutrinos hit the earth every second the neutrinos will be able to reach the detector even though it’s far below the surface.

Still there was one problem to overcome, at the center of the detector necessary for it’s function were carbon-14 atoms. These atoms tend to decay, that is why we have a method called carbon 14 dating were we can estimate the age of organic remains by measuring the amount of carbon-14 remaining. In the detector the decay of the carbon-14 could give false positives, that a neutrino had been detected. Because of this the scientists had to carefully gather data so they could exclude those signals from the real neutrino signals. After multiple years the researchers felt confident enough that they indeed had isolated the signal that indicated that they had in fact detected a solar neutrino.

This discovery further confirms the current theories about how fusion in the sun actually works and give them a sense of how future experiments will be set up to further their knowledge about neutrinos.

 Image credit: Borexino Collaboration