Pion
In particle physics, a pion (or a pi meson, denoted with the Greek letter pi: π) is any of three subatomic particles: π0, π+, and π−. Each pion consists of a quark and an antiquark and is therefore a meson. Pions are the lightest mesons (and, more generally, the lightest hadrons), because they are composed of the lightest quarks (the u and d quarks). They are unstable, with the charged pions π+ and π− decaying with a mean lifetime of 26 nanoseconds (2.6×10−8 seconds), and the neutral pion π0 decaying with a much shorter lifetime of 8.4×10−17 seconds. Charged pions most often decay into muons and muon neutrinos, and neutral pions into gamma rays.
The exchange of virtual pions, along with the vector, rho and omega mesons, provides an explanation for the residual strong force between nucleons. Pions are not produced in radioactive decay, but are produced commonly in high energy accelerators in collisions between hadrons. All types of pions are also produced in natural processes when high energy cosmic ray protons and other hadronic cosmic ray components interact with matter in the Earth's atmosphere. Recently, detection of characteristic gamma rays originating from decay of neutral pions in two supernova remnant stars has shown that pions are produced copiously in supernovas, most probably in conjunction with production of high energy protons that are detected on Earth as cosmic rays.
Latest News for: pion
‘Can’-pions announced in annual food drive
Hickory Record
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Pione Sisto: The Revival
Sportslens 30 Sep 2020Denmark call up Pione Sisto for first time in two years ahead of England clash
Yahoo Daily News 29 Sep 2020Sinosure Shandong Branch and China Export-Import Bank Shandong Branch visited Weiqiao Pion...
Public Technologies 10 Aug 2020Checking in with ... Scott Pion Jr. (St. Bernard/Wheeler)
The Day 01 May 2020Improved Primakoff-type experiment gives improved accuracy of pion measurement
PhysOrg 01 May 2020Celta ask Smolov and Pione Sisto to return in May
BE Soccer 26 Apr 2020Alg�rie: Achrad Hakimi - Autour de la Juventus d'avancer ses pions !
All Africa 01 Apr 2020Celta Vigo winger Pione Sisto drove 1864 MILES from Spain to Denmark during lockdown... breaking ...
The Daily Mail 29 Mar 2020Roger Pion Not Competent To Stand Trial Over Family Threats
Caledonian Record
29 Feb 2020
Celta Vigo 2-1 Sevilla: Substitute Pione Sisto scores late winner as relegation-threatened Celta secure shock victory
The Daily Mail 09 Feb 2020- 1
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