Search results
Results from the WOW.Com Content Network
Feynman diagram of the dominant leptonic pion decay. Kaon decay in a nuclear emulsion. The positively-charged kaon enters at the top of the image and decays into a π − meson (a) and two π + mesons (b and c). The π − meson interacts with a nucleus in the emulsion at B. The π ± mesons have a mass of 139.6 MeV/c 2 and a mean lifetime of 2 ...
In the Stückelberg–Feynman interpretation, pair annihilation is the same process as pair production: Møller scattering: electron-electron scattering Bhabha scattering: electron-positron scattering Penguin diagram: a quark changes flavor via a W or Z loop Tadpole diagram: One loop diagram with one external leg Self-interaction or oyster diagram
The Feynman diagrams are much easier to keep track of than "old-fashioned" terms, because the old-fashioned way treats the particle and antiparticle contributions as separate. Each Feynman diagram is the sum of exponentially many old-fashioned terms, because each internal line can separately represent either a particle or an antiparticle.
The appeal of the Feynman diagrams is strong, as it allows for a simple visual presentation of what would otherwise be a rather arcane and abstract formula. In particular, part of the appeal is that the outgoing legs of a Feynman diagram can be associated with actual, on-shell particles. Thus, it is natural to associate the other lines in the ...
The Feynman diagram for beta-minus decay of a neutron (n = udd) into a proton (p = udu), electron (e −), and electron anti-neutrino ν e, via a charged vector boson (W −). In one type of charged current interaction, a charged lepton (such as an electron or a muon, having a charge of −1) can absorb a W +
Here, a proton, consisting of two up quarks and a down, decays into a pion, consisting of an up and anti-up, and a positron, via an X boson with electric charge − 4 / 3 e. In particle physics, proton decay is a hypothetical form of particle decay in which the proton decays into lighter subatomic particles, such as a neutral pion and a ...
This is a one-loop Feynman diagram. The coupling is a pseudoscalar coupling; the two photons couple as vectors. The triangle sums over all lepton generations. The chiral anomaly originally referred to the anomalous decay rate of the neutral pion, as computed in the current algebra of the chiral model. These calculations suggested that the decay ...
[1] [2] [3] It states that any strongly occurring process will be suppressed if, through only the removal of internal gluon lines, its Feynman diagram can be separated into two disconnected diagrams: one containing all of the initial-state particles and one containing all of the final-state particles.