Plutonium-238
Isotope
Plutonium-238 is a radioactive isotope of plutonium that has a half-life of 87.7 years.
Plutonium-238 is a very powerful alpha emitter; as alpha particles are easily blocked, this makes the plutonium-238 isotope suitable for usage in radioisotope... Wikipedia
Protons: 94
Number of neutrons: 144 neutrons
Half-life (t1/2): 87.7 years
Parent isotopes: 242Cm (α); 238Np (β−); 238Am (β+)