ALPHA PARTICLES (PARTIKEL ALFA)
Alpha particles (named after and denoted by the first letter of the Greek alphabet, α) => positively charged particles emitted by some radioactive elements.
Alpha particle consists of two neutrons bound to two protons, so it is identical to helium nuclei. Alpha particle is one of three types of radiation (alpha, beta, gamma).
Alpha particles are harmless to plants, animals, or humans, unless the alpha-emitting substance has been entered into the body.