a neutral meson having a mass 5832 times that of the electron and a mean lifetime of approximately 3.1 × 10-22 seconds.
Also called eta-c particle.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
An electrically neutral meson having a mass 5,832 times that of the electron and a mean lifetime of approximately 3.1 X 10-22 seconds. See Table at subatomic particle.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.