Here's why:
* Positron emission is a type of radioactive decay where a proton in the nucleus transforms into a neutron, emitting a positron and a neutrino.
* The positron is the antiparticle of the electron, carrying a positive charge.
* The neutrino is a neutral, nearly massless particle that interacts very weakly with matter.
In summary: Positron emission results in the creation of a neutrino to conserve both energy and momentum in the decay process.
