alpha particle


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Related to alpha particle: Gamma particle

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 ?
Assume that neutrons, surrounding an alpha particle before decay of 8He, is polarized the same as in the alpha-particle (1, -2/3, and 1/3).
Alpha particles consist of two protons and two neutrons.
As it can be seen in the radon decay chain, number of alpha particles emitted in this chain is high and given that alpha particle considered as one of the most dangerous particles resulted from decays so this gas can be considered as one of the dangerous radioactive gases.
Caption: Euriosity's two-metre-long robotic arm contains a variety of tools including cameras, a drill, a soil scoop and an alpha particle X-ray spectrophotometer (APXS), visible here as a can-shaped device located at the 10 o'clock position.
3 Gy) are delivered to individual cells that are traversed by a single alpha particle no matter how low the dose to the whole body (Lorimore et al.
The XIA UltraLo-1800 is a low background alpha particle counter that employs electronic background suppression to drive achievable background rates to 0.
The highest peak on the plot is a result of the XASW interaction with the alpha particles oscillating at the first cyclotron harmonic of helium.
It takes a direct hit from just one alpha particle to destroy a lone cancer cell.
You can think of an alpha particle as something like a tiny cannon ball--it does not travel very far (a few centimeters in air), but if it hits a living cell, the but if it hits a living cell, the damage can be enormous.
Inside a cancer cell, the atom decays by giving off high energy alpha particle radiation which tears through the cell's DNA and proteins.
It doesn't help any cell in the human body if you send an alpha particle through it.