Glossary

Warning

These pages are under development.

The glossary can be used to collect terms that require further explanation or linking to literature, but are too general or specific to deserve an own section on these pages.

asymptotic freedom

The fact that the coupling constant of the strong force increases in strength for lower momentum.

baryon

A particle that consists of three quarks.

color confinement

The fact that quarks only exist in colorless, bound states (quark groups of which the colors add up to ‘white’). See also asymptotic freedom.

coupling constant

Todo

Define coupling constant

damping factor

form factor

Often defined with the symbol \(B_{\alpha_i}\).

formation experiment

Experiments where particles \(A\) and \(B\) are collided, resulting in a reaction:

\[ A + B \to R \to C_1 + \dots + C_n, \]

Here, \(R\) is the resonance in which one is often interested in hadron spectroscopy.

See PDG2020, §Resonances [T13]. Related: production experiment.

hadron

Particles that consist of two quarks (meson) or three quarks (baryon).

hadron spectroscopy

Todo

Define hadron spectroscopy

hyperon

A baryon with at least one strange quark.

K-matrix

A real, symmetric and hermitian operator that is defined from the T-matrix through \(K^{-1} = T^{-1} + iI\). See [Chung et al., 1995, Badalyan et al., 1982] and PDG2020, §Resonances [T13].

lattice QCD

A numerical tool with which to study particle interactions mediated by the strong force at low momentum transfer

meson

A particle that consists of two quarks.

P-vector

First described in [Aitchison, 1972]. See also [Chung et al., 1995] and PDG2020, §Resonances [T13].

production experiment

spectator particle

Experiments of the kind:

\[ \begin{align}\begin{aligned}A + B \to R + S \to [C_1 + \dots + C_n] + S\\Z \to R + S \to [C_1 + \dots + C_n] + S\end{aligned}\end{align} \]

Here, \(R\) is the resonance in which one is often interested in hadron spectroscopy, while \(S\) is a spectator particle. The first case is comparable to a formation experiment, while the second represents a decay process of particle \(Z\).

See PDG2020, §Resonances [T13].

Q-vector

See [Chung et al., 1995] and PDG2020, §Resonances [T13].

Quantum Chromodynamics (QCD)

The theory that describes the strong force on the most fundamental level. See PDG2020, §QCD [T13].

quark

Elementary particle that constitutes hadronic matter.

Quark Constituent Model (QCM)

Model with which to describe and categorize matter constituted of quarks (i.e. hadrons). See [T13] (PDG2020, §Quark Model).

resonance

See [T13] (PDG2020, §Resonances).

S-matrix

scattering operator

See [Martin and Spearman, 1970], Ch.4.

Standard Model

Most fundamental description of matter and forces

strong force

One of the four fundamental forces of the Standard Model

T-matrix

transition operator

The scattering operator can split into a non-interacting component \(I\) (identity operator) and a matrix \(T\) that describes the actual interactions through \(S = I + iT\). See [Martin and Spearman, 1970], Ch.4, and [Chung et al., 1995].