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n. A semistable meson produced either in a neutral form with a mass 264 times that of an electron and a mean lifetime of 8.4 × 10-17 seconds or in a positively or negatively charged form with a mass 273 times that of an electron and a mean lifetime of 2.6 × 10-8 seconds. Also called pi meson. See Table at subatomic particle.

n. Any of three semistable mesons, having positive, negative or neutral charge, composed of up and down quarks/antiquarks.

n. a meson involved in holding the nucleus together; produced as the result of high-energy particle collision

"“The pion is usually pictured as a relatively simple system consisting of one quark and one anti-quark,” Dr. Huber says."

meson    mesotron   

pi meson   

ion   

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