- any of a family of mesons consisting of a charmed quark and a charmed antiquark.
- an early name for the J/psi particle.
Origin of psi particle
First recorded in 1970–75
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- See J/psi particle
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- See J/psi particle.
- An electrically neutral meson having a mass 7,213 times that of the electron and a mean lifetime of approximately 1 X 10-20 seconds, composed, like the J/psi particle, of a charm-anticharm quark pair. See Table at subatomic particle.
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