ParticleSelector

Symbolica documentation for getting started, symbolic expressions, numerical evaluation, pattern matching, and APIs in Python and Rust.

`ParticleSelector`

class ParticleSelector

A model-independent way to identify an external particle.

Selectors may use a UFO particle name or a signed PDG code, making process definitions convenient while deferring validation to a concrete model.

Examples

from symbolica.community import hepkit as hep
electron = hep.ParticleSelector.by_pdg(11)
positron = hep.ParticleSelector.by_name("e+")

Attributes

Name	Description
`is_name`	Report whether this selector identifies a particle by name.
`is_pdg`	Report whether this selector identifies a particle by PDG code.
`name`	Return the selected particle name
`pdg`	Return the selected PDG code

`is_name`

ParticleSelector.is_name: builtins.bool

Report whether this selector identifies a particle by name.

Examples

Using the setup in the ParticleSelector class example:

assert hep.ParticleSelector.by_name("e-").is_name

`is_pdg`

ParticleSelector.is_pdg: builtins.bool

Report whether this selector identifies a particle by PDG code.

Examples

Using the setup in the ParticleSelector class example:

assert hep.ParticleSelector.by_pdg(11).is_pdg

`name`

ParticleSelector.name: builtins.str

Return the selected particle name.

Raises :class:TypeError for a PDG selector. Use :attr:is_name to distinguish the selector variants before accessing their payloads.

Examples

Using the setup in the ParticleSelector class example:

assert hep.ParticleSelector.by_name("e-").name == "e-"

`pdg`

ParticleSelector.pdg: builtins.int

Return the selected PDG code.

Raises :class:TypeError for a name selector. Use :attr:is_pdg to distinguish the selector variants before accessing their payloads.

Examples

Using the setup in the ParticleSelector class example:

assert hep.ParticleSelector.by_pdg(11).pdg == 11

Methods

Name	Description
`__eq__`	Compare with another selector, a particle name, or a PDG code.
`__repr__`	Return a constructor-style representation of the selector.
`__str__`	Format the selector as its particle name or signed PDG code.
`by_name`	Select a particle by its model name.
`by_pdg`	Select a particle by its signed PDG code.

`eq`

ParticleSelector.__eq__(other: typing.Any) -> builtins.bool

Compare with another selector, a particle name, or a PDG code.

Examples

Using the setup in the ParticleSelector class example:

hep.ParticleSelector.by_pdg(11) == 11
True

Parameters

other (object) Selector, particle-name string, or integer PDG code to compare with.

`repr`

ParticleSelector.__repr__() -> builtins.str

Return a constructor-style representation of the selector.

Examples

Using the setup in the ParticleSelector class example:

print(hep.ParticleSelector.by_pdg(11))  # electron selector in a process

`str`

ParticleSelector.__str__() -> builtins.str

Format the selector as its particle name or signed PDG code.

Examples

Using the setup in the ParticleSelector class example:

str(hep.ParticleSelector.by_pdg(11))
'11'

`by_name`

ParticleSelector.by_name(name: builtins.str) -> ParticleSelector

Select a particle by its model name.

Examples

Using the setup in the ParticleSelector class example:

hep.ParticleSelector.by_name("e-").name
'e-'

Parameters

name (str) Particle name as it appears in the model.

`by_pdg`

ParticleSelector.by_pdg(pdg: builtins.int) -> ParticleSelector

Select a particle by its signed PDG code.

Examples

Using the setup in the ParticleSelector class example:

hep.ParticleSelector.by_pdg(11).pdg
11

Parameters

pdg (int) Signed PDG code of the particle.