- a neutral meson with strangeness 0 that is its own antiparticle. Symbol: η
Origin of eta meson
First recorded in 1960–65
Also called eta particle.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- An electrically neutral meson having a mass 1,071 times that of the electron and a mean lifetime of approximately 3.5 X 10-8 seconds. See Table at subatomic particle.
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