Proposed by Pauli to make beta decay satisfy conservation laws, for 10 points, what are these weakly-interacting low-mass lepton cousins of the tau, muon, and electron?
In the MSW effect, they experience coherent forward scattering in the presence of electrons, and their production in nuclei is governed by the Gamow-Teller selection rules, including no change in nuclear parity. Despite their slower velocities, ones from Supernova 1987a reached Earth before photons from the same event because of their failure to interact electromagnetically on the way. With intrinsic spin virtually always opposite their direction of travel, these "left-handed" candidate components of hot dark matter have been shown to change flavors between the Sun and Earth and thus must have nonzero mass. Proposed by Pauli to make beta decay satisfy conservation laws, for 10 points, what are these weakly-interacting low-mass lepton cousins of the tau, muon, and electron?
In the MSW effect, they experience coherent forward scattering in the presence of electrons, and their production in nuclei is governed by the Gamow-Teller selection rules, including no change in nuclear parity.
{neutrino}s (accept {antineutrino}s up to “opposite” and do not prompt thereafter: antineutrinos are right-handed, or with spin pointing in the direction of travel)