What are some common unstable subatomic particles and their lifetimes?

Most subatomic particles are unstable, meaning they do not exist for long. They quickly decay into other, lighter, and more stable particles (like electrons, protons, and neutrinos). The "lifetime" of a particle is a statistical average of how long it exists before decaying.

Here is a list of common unstable subatomic particles and their approximate mean lifetimes.

• Free Neutron (n)
  • Lifetime: ~879.6 seconds (about 14.7 minutes)
  • Note: While neutrons are stable inside the nucleus of an atom, a neutron on its own will decay into a proton, an electron, and an antineutrino.
• Muon (μ⁻)
  • Lifetime: 2.2 microseconds (2.2 x 10^-6 seconds)
  • Note: A muon is a lepton, like a heavier version of the electron. It decays into an electron, a muon neutrino, and an electron antineutrino.
• Charged Pion (π⁺, π⁻)
  • Lifetime: 26 nanoseconds (2.6 x 10^-8 seconds)
  • Note: Pions are mesons (particles made of a quark and an antiquark) that help mediate the strong force between nucleons.
• Tau Lepton (τ⁻)
  • Lifetime: 0.29 picoseconds (2.9 x 10^-13 seconds)
  • Note: An even heavier "cousin" of the electron and muon. Its extremely short lifetime is due to its large mass, which allows it to decay in many different ways.
• Neutral Pion (π⁰)
  • Lifetime: 85 attoseconds (8.5 x 10^-17 seconds)
  • Note: This pion decays much faster than its charged counterparts, typically into two high-energy photons (gamma rays).
• Z Boson (Z⁰)
  • Lifetime: 3 x 10^-25 seconds
  • Note: The force carriers of the weak force are themselves unstable due to their immense mass.