Interactive examples¶
This page exposes some of the functionality of the expertsystem as online utilities.
Quantum number search¶
The load_pdg function creates a ParticleCollection containing the latest PDG info. Its find and filter methods allows you to quickly look up the quantum numbers of a particle and, vice versa, look up particle candidates based on a set of quantum numbers.
import expertsystem as es
pdg = es.io.load_pdg()
pdg.find(22)
pdg.find("Delta(1920)++")
subset = pdg.filter(lambda p: p.spin in [2.5, 3.5, 4.5] and p.name.startswith("N"))
subset.names
Tip
Check allowed reactions¶
The expertsystem can be used to check whether a transition between an initial and final state is violated by any conservation rules:
import expertsystem as es
es.check_reaction_violations(
initial_state="pi0",
final_state=["gamma", "gamma", "gamma"],
)
Investigate intermediate resonances¶
The expertsystem is designed to be a tool when doing Partial Wave Analysis. Its main features are therefore the generate_transitions and generate_amplitudes functions. Here’s a small applet with which to visualize these transitions online:
from graphviz import Source
import expertsystem as es
result = es.generate_transitions(
initial_state=("J/psi(1S)", [-1, +1]),
final_state=["p", "p~", "eta"],
allowed_interaction_types="strong",
)
graphs = result.collapse_graphs()
Source(es.io.convert_to_dot(graphs))
This example takes around 2 minutes to compute on Binder.
Tip
See Usage and Create amplitude models