the first meson to be discovered: it has spin 0 and may be positively or negatively charged or neutral; charged pions decay into a muon and a neutrino or antineutrino. Symbol: π
- Also called pi meson.
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How to use pion in a sentence
Specifically, the proton morphs into a neutron and a pion made of one up quark and one down antiquark.Decades-Long Quest Reveals Details of the Proton’s Inner Antimatter | Natalie Wolchover | February 24, 2021 | Quanta Magazine
The pion saplings, which the dancers also pretended to swallow, had no deceptive arrangement.The Mountain Chant, A Navajo Ceremony | Washington Matthews
In reality, each boy is an unpaid pion, a watchdog whose vigilance never relaxes.The Secret Glory | Arthur Machen
pion; A certaine great, round, and Bulbus-rooted flower, of one whole colour.The plant-lore and garden-craft of Shakespeare | Henry Nicholson Ellacombe
Close at hand was a pion tree, which spread out low-growing branches all about.The Motor Rangers Through the Sierras | Marvin West
Both the pion and the camass are largely utilized even at the present day for food by the Indians.North America | Israel C. Russell
British Dictionary definitions for pion
physics a meson having a positive or negative charge and a rest mass 273.13 times that of the electron, or no charge and a rest mass 264.14 times that of the electron
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
Scientific definitions for pion
A meson occurring either in a neutral form with a mass 264 times that of an electron and a mean lifetime of 8.4 X 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 X 10-8 seconds. The pion was once believed to be the particle that mediates the strong force, which holds nucleons together in the nucleus; it is now believed that the gluon is the mediator particle. Pions do interact with nucleons, however, and are able to transform neutrons into protons and vice versa. Also called pi-meson See Table at subatomic particle.
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