Lighter unstable isotopes of samarium primarily decay by electron capture to isotopes of promethium, while heavier ones convert through beta decay to isotopes of europium.
The initial collapse of degenerate cores is accelerated by beta decay, photodisintegration and electron capture, which causes a burst of electron neutrinos.
Nuclides that lie up the walls of the valley tend to decay by beta decay towards the center (by emitting an electron, emitting a positron, or capturing an electron).
Tritium emits electrons through beta decay, and, when they interact with a phosphor material, fluorescent light is created, a process called radioluminescence.