eta particle

American  

noun

1. Physics. a meson with a neutral charge, a mass 1,071 times that of the electron, and an approximate mean lifetime of 3.5 × 10^-8 seconds.

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eta particle Scientific  

/ ā′tə,ē′tə /

1. An electrically neutral meson having a mass 1,071 times that of the electron and a mean lifetime of approximately 3.5 × 10 ^{- 8} seconds.

2. See Table at subatomic particle

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