Long-sought particles confirm a fusion reaction that helps power the sun
In a technical tour de force, physicists have spotted long-sought low-energy neutrinos zipping from the sun. The discovery confirms one of the first possible steps in the fusion cycle that helps power the star, says Cristiano Galbiati, a physicist at Princeton University and member of the large international team that reports the discovery February 2 in Physical Review Letters.
The newfound particles are produced when two protons and an electron interact to make deuterium, a heavy form of hydrogen that helps feed the sun’s fusion. About 1 in 400 deuterium atoms in the sun are made in this proton-electron-proton, or pep, reaction.