How is the weak force involved in radioactive decay and the energy of stars?

The weak force is a fundamental interaction that plays a critical role in both radioactive decay and the energy production of stars.1

Radioactive Decay

The weak force is responsible for beta decay, a process in which an unstable nucleus transforms by changing the flavor of its subatomic particles. For example, a neutron can transmute into a proton by emitting a virtual W particle, which then decays into an electron and an antineutrino. Because the W particle is extremely massive, its range is limited to less than ${10}^{-17}$ meters, making the weak force appear feeble at low energies.12

Stellar Energy

In the Sun and other stars, the weak force initiates the nuclear fusion process that powers them. Specifically, it allows two protons to interact and form a deuterium nucleus. This reaction is the first step in the proton-proton chain, which ultimately converts hydrogen into helium, releasing the vast amounts of energy that sustain stellar life.13