a meson with a mass 6687 times that of the electron and a mean lifetime of approximately 1.5 X 10-20 seconds.
Also called chi particle.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
An electrically neutral meson having a mass 6,687 times that of the electron and a mean lifetime of approximately 1.5 X 10-20 seconds. See Table at subatomic particle.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.