pion

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pi·on

(pī′ŏn′)

Any of the three least massive mesons, having a positive, neutral, or negative electric charge. The charged pions have a mass 273 times that of an electron and a mean lifetime of 2.6 × 10^-8 second, and the neutral pion has a mass 264 times that of an electron and a mean lifetime of 8.4 × 10^-17 second. Also called pi meson.

[Contraction of pi meson.]

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

pion

(ˈpaɪɒn) or

pi meson

(General Physics) 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

[C20: from Greek letter pi¹ + on]

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

pi•on

(ˈpaɪ ɒn)

n.

any of the three lightest mesons, having positive, negative, or neutral electric charge and spin of zero.

[1950–55; pi (meson) + -on¹]

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Noun

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

pi-meson

meson, mesotron - an elementary particle responsible for the forces in the atomic nucleus; a hadron with a baryon number of 0

Translations

pion

References in classic literature ?

John, and was formerly Christian Church ;) further toward you is the hill of Pion, around whose front is clustered all that remains of the ruins of Ephesus that still stand; divided from it by a narrow valley is the long, rocky, rugged mountain of Coressus.

In the Mount of Pion, yonder, is the Cave of the Seven Sleepers.

Paul, where we all did use to go to touch the ancient chains that bound him and be cured of our distempers; I see the tomb of the disciple Luke, and afar off is the church wherein repose the ashes of the holy John, where the Christians of Ephesus go twice a year to gather the dust from the tomb, which is able to make bodies whole again that are corrupted by disease, and cleanse the soul from sin; but see how the wharves encroach upon the sea, and what multitudes of ships are anchored in the bay; see, also, how the city hath stretched abroad, far over the valley behind Pion, and even unto the walls of Ayassalook; and lo, all the hills are white with palaces and ribbed with colonnades of marble.

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From Quarks to Pions: Chiral Symmetry and Confinement

In high-energy collisions along with the pions, kaons are also important as the strange particle production is a powerful probe into the hadronic interaction and the hadronization process in pp and heavy-ion collisions at relativistic energies.

A Comparative Study of [K.sup.[+ or -]]/[[pi].sup.[+ or -]] Ratio in Proton-Proton Collisions at Different Energies: Experimental Results versus Model Simulation

must be -Stan pions f The feature, the Champions Stakes, is the jewel in the crown of a mouth-watering card.

DOUBLE HANDFUL

Car l'antre blanche ne le sait que trop bien, la difference de niveau, abyssale, appelle de nouveaux pions blaugrana.

Les Blaugrana humilient les Merengues a Bernabeu

Scientists can't tell if a gamma ray entering a detector is a high-energy proton or a high-energy electron.To see if supernovae could be the source of cosmic rays, the scientists were looking for traces of pions, a subatomic particle made when cosmic rays interact with the dust and gas around a supernova.

Mystery Of Cosmic Ray Origin Solved: Fast-Moving Protons Forged In Supernovae

They interact with the matter and produce pions which in their turn decay and generate high-energy gamma-rays with specific spectrum [4, 5].

On the onset time of several SPE/GLE events: indications from high-energy gamma-ray and neutron measurements by CORONAS-F

Hence, in order to avoid contradictions with the existence of charged pions and [W.sup.[+ or -]], one must demand that the pions and the [W.sup.[+ or -]] are composite particles.

Quantum constraints on a charged particle structure

Neutrinos in this experiment are emitted in the decay of subatomic particles called pions; the pions possess far less energy than the amount required by the neutrinos to exceed light speed.