pγ → ηπ⁰p

Amplitude Analysis 101 / PWA101 (v2.0)

CAS-assisted Amplitude Models building for photoproduction reaction

This document is a follow-up of PWA101 (v1.0), see TR‑033.

The tutorial has been split into separate notebooks and the amplitude model is instead formulated using CAS-assisted (Computer Algebra System) model building using SymPy and the ComPWA packages.

In the following, an attempt to manually formulate the amplitude model via Sympy is shown. Later on, attempts of automated amplitude model formualtion are done via e.g. ampform and ampform-dpd.

• Reaction and Models
  • Reaction with Resonances and Decay
  • Amplitude Models
• Amplitude model with sympy
  • Model implementation
    • \(A^{12}\)
    • \(A^{23}\)
    • \(A^{31}\)
    • \(I = |A|^2 = |A^{12}+A^{23}+A^{31}|^2\)
    • Phase Space Generation
    • Kinematic variables
    • Parameters
  • Visualization
    • Model components
    • Dalitz Plot
    • Projection
• Reaction via qrules
  • Finding particles
    • Proton
    • \(\gamma\)
    • \(\eta\)
    • \(\pi^0\)
• Virtual particle that represents the state pγ
  • Adding custom particle
• Amplitude model with ampform
  • Generate transitions
  • Formulate model
  • Visualization