- The Borexino experiment, which has been operating from beneath the earth from Italy’s Gran Sasso Laboratory for the last seven years, has detected the lowest energy neutrino branch which accounts for 90 per cent of the total flux.
- Sun’s energy is generated by a nuclear reaction involving the fusion of a pair of protons to produce Helium nuclei. The process also generates neutrinos.
- Neutrinos come in 3 types, electron neutrino, muon neutrino and the tau neutrino. The ones travelling away from the Sun’s core are electron neutrinos. These can oscillate and change into the other 2 types as they travel away from the core.
- In the early experiments, the number of solar neutrinos detected were at least half less than what was predicted. They explained the missing neutrinos by using the model where the neutrinos oscillate into other types (or flavours, namely the muon and tau neutrinos) before reaching the earth.
- Borexino is located deep beneath the Apennine Mountains and detects neutrinos as they interact with the electrons of an ultra-pure organic liquid scintillator at the centre of a large sphere surrounded by 1,000 tons of water.
- It is the only detector on Earth capable of observing the entire spectrum of solar neutrinos simultaneously.
- Read at: http://www.thehindu.com/todays-paper/tp-features/tp-sci-tech-and-agri/solar-neutrinos-messengers-from-within/article6358278.ece