Beta Decay

Beta decay is the most common type of radioactive decay, observed in over 97% of all known unstable nuclides.

It is where a nucleus transforms by emitting a beta particle (an electron or anti-electron) and an antineutrino or neutrino.

This is the easiest way to see the Law of Conservation of Substance at work.

There are 3 Types of Beta Decay.0

1. β⁻ Decay (Electron Emission)

A neutron converts into a proton, emitting an electron and an electron-antineutrino. The atomic number increases by 1, mass number unchanged.

2. β⁺ Decay (Positron Emission)

A proton converts into a neutron, emitting an anti-electron and an electron-neutrino. The atomic number decreases by 1.

3. Electron Capture

A proton-rich nucleus absorbs an inner-shell electron, which combines with a proton to form a neutron and emit a neutrino.

Examples

Practical Applications

• Radiocarbon dating – Carbon-14 beta decay measures the age of organic artifacts.
• PET scans – Positron-emitting isotopes like Fluorine-18 annihilate with electrons, producing gamma rays for medical imaging.
• Nuclear reactors – Beta decay of fission products produces delayed neutrons essential for reactor control.
• Betavoltaic batteries – Beta particles generate electricity in long-lasting pacemaker batteries.