What is alpha particle

Dear Student
Alpha particles are a type of ionizing radiation ejected by the nuclei of some unstable atoms. They are large subatomic fragments. Alpha particle consists of two protons and two neutrons bound together into a particle identical to a helium nucleus. The symbols used for alpha particles are  and can be written as .

They are positively charged particles (ions) hence they show deflection, that too at very wide angles.
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