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α粒子 (アルファりゅうし) Japanese meaning | Kotomora

α粒子あるふぁりゅうし

ア

ル

ファ

りゅ

う

し

Meanings

1

alpha particle

Physics term for a helium-4 nucleus emitted during alpha decay.

α粒りゅう子しはヘリウムの原げん子し核かくである。
An alpha particle is a helium nucleus.

ラジウムはα粒りゅう子しを放ほう出しゅつして崩ほう壊かいする。

Radium decays by emitting alpha particles.

Kanji

粒grains, drop, counter for tiny particles
子child, sign of the rat, 11PM-1AM

Related words

β粒子べーたりゅうし
Beta particle (electron or positron), lighter and more penetrating than an alpha particle.
γ線がんません
Gamma ray, electromagnetic radiation, more penetrating than alpha particles.

Written forms

α粒子あるふぁりゅうし
Standard scientific notation using the Greek letter alpha.
アルファ粒りゅう子し
Kana spelling of the alpha part; common in less technical contexts or when Greek letters are unavailable.

Etymology

Compound of α (alpha) + 粒子 (particle). The term is a direct calque from English 'alpha particle'.