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.particle.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 reaction
and amplitude
modules. Here’s a small applet with which to visualize these transitions online:
import expertsystem as es
import graphviz
result = es.generate_transitions(
initial_state=("J/psi(1S)", [-1, +1]),
final_state=["p", "p~", "eta"],
allowed_interaction_types="strong",
formalism_type="canonical-helicity",
)
graphviz.Source(es.io.asdot(result, collapse_graphs=True))
Tip
See Usage, Generate transitions and Formulate amplitude model