alpha particle

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alpha particle

n.
A positively charged subatomic particle, composed of two protons and two neutrons, identical with the nucleus of the helium isotope He-4.

alpha particle

n
(General Physics) a helium-4 nucleus, containing two neutrons and two protons, emitted during some radioactive transformations

al′pha par`ticle


n.
a positively charged particle consisting of two protons and two neutrons, emitted in radioactive decay or nuclear fission; the nucleus of a helium atom.
[1900–05]

alpha particle

A positively charged particle that consists of two protons and two neutrons bound together. It is emitted by the nucleus of some elements undergoing radioactive decay and is identical to the nucleus of a helium atom. Alpha particles are the slowest and least penetrating forms of nuclear radiation. ♦ The process by which a radioactive element emits an alpha particle is called alpha decay. Alpha decay results in the atomic number of the atom being decreased by two and the mass number being decreased by four. See more at radiation, radioactive decay.

alpha particle

A helium nucleus that has a positive electric charge.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.alpha particle - a positively charged particle that is the nucleus of the helium atomalpha particle - a positively charged particle that is the nucleus of the helium atom; emitted from natural or radioactive isotopes
subatomic particle, particle - a body having finite mass and internal structure but negligible dimensions
References in periodicals archive ?
In the case of the sun (as in the case of most stars), it is two hydrogen nuclei fusing to form a helium nucleus.
Deuterium and tritium nuclei combine, forming a helium nucleus, a neutron and a lot of energy.
When deuterium and tritium nuclei - which can be found in hydrogen - fuse, they form a helium nucleus, a neutron and a lot of energy.
Each D -T reaction produces a helium nucleus (two protons and two neutrons) plus a neutron.
Similar to what happens in the sun or a star, when deuterium and tritium nuclei are fused at high temperatures and pressures, they form a helium nucleus, a neutron--and huge amounts of energy.
The energy from a single deuteriumtritium fusion reaction is carried away by a neutron and a helium nucleus.
The enormous pressure created by a star's mass causes pairs of hydrogen nuclei in its core to fuse into a helium nucleus, thereby converting a small amount of mass into energy.
In the second case muon sticks to helium nucleus and helium ion ( is formed and extra energy is released through g- hannel.