- an unstable hyperon having positive, negative, or zero electric charge and strangeness −1. Symbol: Σ
Origin of sigma particle
First recorded in 1960–65
Also called sigma baryon.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- Any of three unstable subatomic particles in the baryon family, having a mass 2,328 to 2,343 times that of the electron and a positive, neutral, or negative electron charge. See Table at subatomic particle.
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