Deprecated since version 0.7.3: Use QRules and AmpForm instead

import expertsystem.amplitude.helicity

Generate an amplitude model with the helicity formalism.

class CanonicalAmplitudeBuilder(reaction_result: Result)[source]

Bases: expertsystem.amplitude.helicity.HelicityAmplitudeBuilder

Amplitude model generator for the canonical helicity formalism.

This class defines a full amplitude in the canonical formalism, using the helicity formalism as a foundation. The key here is that we take the full helicity intensity as a template, and just exchange the helicity amplitudes \(F\) as a sum of canonical amplitudes \(A\):

\[F^J_{\lambda_1,\lambda_2} = \sum_{LS} \mathrm{norm}(A^J_{LS})C^2.\]

Here, \(C\) stands for Clebsch-Gordan factor.

class HelicityAmplitudeBuilder(reaction_result: Result)[source]

Bases: object

Amplitude model generator for the helicity formalism.

set_dynamics(particle_name: str, dynamics_builder: ResonanceDynamicsBuilder)None[source]
class HelicityModel(expression: Expr, parameter_defaults: Dict[Symbol, Union[float, complex, int]], components: Dict[str, Expr], adapter: HelicityAdapter, particles: ParticleCollection)[source]

Bases: object


Method generated by attrs for class HelicityModel.

property adapter
property components
property expression
property parameter_defaults
particles: ParticleCollection
class State(particle: Particle, spin_projection)[source]

Bases: object


Method generated by attrs for class State.

particle: Particle
spin_projection: float