AmpForm is a Python library of spin formalisms and dynamics with which you can automatically formulate symbolic amplitude models for Partial Wave Analysis. The resulting amplitude models are formulated with SymPy (a Computer Algebra System). This not only makes it easy to inspect and visualize the resulting amplitude models, but also means the amplitude models can be used as templates for faster computational back-ends (see TensorWaves)!

Visit ampform.rtfd.io for several usage examples. For an overview of upcoming releases and planned functionality, see here.

• Automatic amplitude model building
  Convert state transition graphs from QRules to an amplitude model that is mathematically expressed with SymPy and can be converted to any backend (see TensorWaves).
• Spin formalisms
  • Helicity formalism
  • Canonical formalism
  • Spin alignment for generic, multi-body decays that feature different decay topologies
• Dynamics
  • Relativistic Breit-Wigner, optionally with form factors and/or energy-dependent width
  • Symbolic K-matrix for an arbitrary number of poles and channels
  • Symbolic P-vector for an arbitrary number of poles and channels

See CONTRIBUTING.md