Enum Topology 

pub enum Topology {
    Full {
        k1: P4Selection,
        k2: P4Selection,
        k3: P4Selection,
        k4: P4Selection,
    },
    MissingK1 {
        k2: P4Selection,
        k3: P4Selection,
        k4: P4Selection,
    },
    MissingK2 {
        k1: P4Selection,
        k3: P4Selection,
        k4: P4Selection,
    },
    MissingK3 {
        k1: P4Selection,
        k2: P4Selection,
        k4: P4Selection,
    },
    MissingK4 {
        k1: P4Selection,
        k2: P4Selection,
        k3: P4Selection,
    },
}

A reusable 2-to-2 reaction description shared by several kinematic variables.

A topology records the four canonical vertices $k_1 + k_2 \to k_3 + k_4$. When one vertex is omitted, it is reconstructed by enforcing four-momentum conservation, which is unambiguous in that frame. Use Topology::com_boost_vector and the *_com helpers to access particles in the center-of-momentum frame.

k1  k3
 ╲  ╱
  ╭╮
  ╰╯
 ╱  ╲
k2  k4

Note that variables are typically designed to use $k_1$ as the incoming beam, $k_2$ as a target, $k_3$ as some resonance, and $k_4$ as the recoiling target particle, but this notation should be extensible to any 2-to-2 reaction.

Variants

Full

All four vertices are explicitly provided.

Fields

k1: P4Selection

First incoming vertex.

k2: P4Selection

Second incoming vertex.

k3: P4Selection

First outgoing vertex.

k4: P4Selection

Second outgoing vertex.

MissingK1

The first incoming vertex (k1) is reconstructed.

Fields

k2: P4Selection

Second incoming vertex.

k3: P4Selection

First outgoing vertex.

k4: P4Selection

Second outgoing vertex.

MissingK2

The second incoming vertex (k2) is reconstructed.

Fields

k1: P4Selection

First incoming vertex.

k3: P4Selection

First outgoing vertex.

k4: P4Selection

Second outgoing vertex.

MissingK3

The first outgoing vertex (k3) is reconstructed.

Fields

k1: P4Selection

First incoming vertex.

k2: P4Selection

Second incoming vertex.

k4: P4Selection

Second outgoing vertex.

MissingK4

The second outgoing vertex (k4) is reconstructed.

Fields

k1: P4Selection

First incoming vertex.

k2: P4Selection

Second incoming vertex.

k3: P4Selection

First outgoing vertex.

Implementations

impl Topology

pub fn new<K1, K2, K3, K4>(k1: K1, k2: K2, k3: K3, k4: K4) -> Self

where K1: IntoP4Selection, K2: IntoP4Selection, K3: IntoP4Selection, K4: IntoP4Selection,

Construct a topology with all four vertices explicitly defined.

pub fn missing_k1<K2, K3, K4>(k2: K2, k3: K3, k4: K4) -> Self

where K2: IntoP4Selection, K3: IntoP4Selection, K4: IntoP4Selection,

Construct a topology when the first incoming vertex (k1) is omitted.

pub fn missing_k2<K1, K3, K4>(k1: K1, k3: K3, k4: K4) -> Self

where K1: IntoP4Selection, K3: IntoP4Selection, K4: IntoP4Selection,

Construct a topology when the second incoming vertex (k2) is omitted.

pub fn missing_k3<K1, K2, K4>(k1: K1, k2: K2, k4: K4) -> Self

where K1: IntoP4Selection, K2: IntoP4Selection, K4: IntoP4Selection,

Construct a topology when the first outgoing vertex (k3) is omitted.

pub fn missing_k4<K1, K2, K3>(k1: K1, k2: K2, k3: K3) -> Self

where K1: IntoP4Selection, K2: IntoP4Selection, K3: IntoP4Selection,

Construct a topology when the second outgoing vertex (k4) is omitted.

pub fn bind(&mut self, metadata: &DatasetMetadata) -> LadduResult<()>

Bind every vertex to dataset metadata so the particle names resolve to indices.

pub fn com_boost_vector(&self, event: &EventData) -> Vec3

Return the velocity vector that boosts lab-frame momenta into the diagram’s center-of-momentum frame.

pub fn k1(&self, event: &EventData) -> Vec4

Convenience helper returning the beam four-momentum (k1).

pub fn k2(&self, event: &EventData) -> Vec4

Convenience helper returning the target four-momentum (k2).

pub fn k3(&self, event: &EventData) -> Vec4

Convenience helper returning the resonance four-momentum (k3).

pub fn k4(&self, event: &EventData) -> Vec4

Convenience helper returning the recoil four-momentum (k4).

pub fn k1_com(&self, event: &EventData) -> Vec4

Beam four-momentum (k1) expressed in the center-of-momentum frame.

pub fn k2_com(&self, event: &EventData) -> Vec4

Target four-momentum (k2) expressed in the center-of-momentum frame.

pub fn k3_com(&self, event: &EventData) -> Vec4

Resonance four-momentum (k3) expressed in the center-of-momentum frame.

pub fn k4_com(&self, event: &EventData) -> Vec4

Recoil four-momentum (k4) expressed in the center-of-momentum frame.

pub fn k1_names(&self) -> Option<&[String]>

Returns the resolved names for k1 if it was explicitly provided.

pub fn k2_names(&self) -> Option<&[String]>

Returns the resolved names for k2 if it was explicitly provided.

pub fn k3_names(&self) -> Option<&[String]>

Returns the resolved names for k3 if it was explicitly provided.

pub fn k4_names(&self) -> Option<&[String]>

Returns the resolved names for k4 if it was explicitly provided.

Trait Implementations

impl Clone for Topology

fn clone(&self) -> Topology

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Topology

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Topology

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Topology

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Serialize for Topology

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.