11.1.7—The composition, mass and charge of α-, β- and γ-radiations (both β–

Alpha radiation is helium nuclei, beta-minus is electrons, beta-plus is positrons, and gamma is high-energy electromagnetic radiation.

Compare mass, charge, ionising power and penetration only after identifying the particle or photon; beta signs depend on β− or β+.

An alpha particle has charge +2e and large mass; a beta-minus particle has charge −e and tiny mass; a gamma photon has zero rest mass and charge.

Gamma is not a stream of neutral nucleons, and beta-plus is not an electron with the usual negative charge.