Public Interface
Functions
ComputableDAGs.graph
— Functiongraph(proc::AbstractProcessDefinition)
Generate and return a ComputableDAGs.DAG
, representing the computation for the squared matrix element of this scattering process, summed over spin and polarization combinations allowed by the process.
QEDFeynmanDiagrams.number_of_diagrams
— Functionnumber_of_diagrams(proc::AbstractProcessDefinition)
For a given QEDbase.AbstractProcessDefinition
, returns the number of valid Feynman diagrams at tree-level. This is equivalent to
\[\frac{(M + 3N - 3)!}{(2N - 1)!} * E! * U! * T!\]
, where
$M \dots$ number of external photons,
$E \dots$ number of electron lines,
$U \dots$ number of muon lines,
$T \dots$ number of tauon lines, and
$N = E + U + T$.
An electron/muon/tauon "line" is a pair of incoming fermion and outgoing anti-fermion or vice versa.