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Glite Dictionary
alpha particle

alpha particle

2 5.8
A small positively charged part of an atom with two protons and two neutrons released in radioactive decay
  • noun
  • /ˈæl.fə ˈpɑːr.tɪ.kəl/
  • Specialized
translation icon : partícula alfa
  • During the test, we measured the intensity of the alpha particles released from the radioactive source.
  • protons and alpha particles
  • alpha particles (helium nuclei)
  • alpha particles (helium)

It's like tissue paper, but yet these alpha particles are bouncing off something.

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Examples

  • The effect would be greatest on the alpha particles since they can travel only a few centimeters in the air.

    Blog text (5)

  • Alpha particles also ionize atoms in their path, setting electrons in motion which cause further ionization.

    Blog text (8)

  • OK, Have all the alpha particles been launched?

  • Strong concentrations of alpha particles on the second level.

    Gog (1954)

  • Created two alpha particles flying off in roughly opposite directions.

    Academic text (2012)

  • Plutonium-238 has a half-life of 88 years and emits alpha particles.

    Blog text (25)

  • Under the conditions, the two types of nuclei fuse together, releasing considerable energy to produce a helium nucleus, known as an alpha particle, and a high-energy neutron.

    Academic text (2002)

  • Plutonium isotopes emit alpha particles, gamma rays, and characteristic x-rays released in atomic transitions of bound electrons.

    Academic text (2004)

  • In 1918, Rutherford bombarded nitrogen atoms with alpha particles (helium nuclei), thus converting nitrogen to oxygen plus a liberated hydrogen nucleus.

    Academic text (2012)

  • The experiment showed that alpha particles can easily pass through thin materials but are stopped by paper.

Surface Forms

alpha particle singular
alpha particles plural

Morphology

alpha + particle

A B1 learner who knows 'alpha' as a label for a first or distinct type and 'particle' as a tiny physical bit can infer that an 'alpha particle' is a particular kind of particle, so the compound is partially compositional. However, the specific technical sense (a helium nucleus with two protons and two neutrons and a positive charge) is specialized scientific knowledge not derivable from the constituents alone, making full understanding unlikely without domain exposure.

Etymology

Alpha particle gets its name from early scientists who used Greek letters to name three kinds of radiation; they called the weakest one 'alpha' and later found it was the nucleus of a helium atom. That's why alpha particle means a heavy, positively charged particle made of two protons and two neutrons.