The Gluon

Electron Positron ◽

This chapter describes the description of the proton as a bound state of partons. After a review of the properties of parton distribution functions, it introduces the evidence for a component of the proton responsible for its binding. It introduces the model of strong interactions as mediated by a spin 1 gluon and presents the evidence for this model from event shapes in electron-positron annihilation to hadrons.

Event shapes and jet rates in electron-positron annihilation at NNLO

Journal of High Energy Physics ◽

10.1088/1126-6708/2009/06/041 ◽

2009 ◽

Vol 2009 (06) ◽

pp. 041-041 ◽

Cited By ~ 85

Author(s):

Stefan Weinzierl

Keyword(s):

Positron Annihilation ◽

Electron Positron ◽

EERAD3: Event shapes and jet rates in electron–positron annihilation at orderαs3

Computer Physics Communications ◽

10.1016/j.cpc.2014.07.024 ◽

2014 ◽

Vol 185 (12) ◽

pp. 3331-3340 ◽

Cited By ~ 24

Author(s):

A. Gehrmann-De Ridder ◽

T. Gehrmann ◽

E.W.N. Glover ◽

G. Heinrich

Keyword(s):

Positron Annihilation ◽

Electron Positron ◽

Parity-odd parton distribution functions from 𝜃-vacuum

International Journal of Modern Physics A ◽

10.1142/s0217751x19501458 ◽

2019 ◽

Vol 34 (26) ◽

pp. 1950145 ◽

Cited By ~ 1

Author(s):

Weihua Yang

Keyword(s):

Quantum Chromodynamics ◽

Parton Distribution ◽

Vacuum State ◽

High Energy ◽

Distribution Functions ◽

Point Of View ◽

Strong Interactions ◽

Parton Distribution Functions ◽

Linear Superposition ◽

Abelian Gauge

Quantum chromodynamics is a fundamental non-Abelian gauge theory of strong interactions. The physical quantum chromodynamics vacuum state is a linear superposition of the [Formula: see text]-vacua states with different topological numbers. Because of the configuration of the gauge fields, the tunneling events can induce the local parity-odd domains. Those interactions that occur in these domains can be affected by these effects. Considering the hadron (nucleon) system, we introduce the parity-odd parton distribution functions in order to describe the parity-odd structures inside the hadron in this paper. We obtain 8 parity-odd parton distribution functions at leading twist for spin-1/2 hadrons and present their properties. By introducing the parity-odd quark–quark correlator, we find the parity-odd effects vanish from the macroscopic point of view. In this paper, we consider the high energy semi-inclusive deeply inelastic scattering process to investigate parity-odd effects by calculating the spin asymmetries.

Partons and Jets

Concepts of Elementary Particle Physics ◽

10.1093/oso/9780198812180.003.0012 ◽

2019 ◽

pp. 187-198

Author(s):

Michael E. Peskin

Keyword(s):

Quantum Chromodynamics ◽

Positron Annihilation ◽

Parton Distributions ◽

Electron Positron ◽

This chapter discusses the predictions of Quantum Chromodynamics for event shapes in electron-positron annihilation to hadrons, and in for the evolution of parton distributions, and the comparison of these predictions to experiment. It introduces the notion of a jet of hadrons associated with a hard-scattered parton.

On factorisation schemes for the electron parton distribution functions in QED

Journal of High Energy Physics ◽

10.1007/jhep07(2021)180 ◽

2021 ◽

Vol 2021 (7) ◽

Author(s):

S. Frixione

Keyword(s):

Analytical Solutions ◽

Parton Distribution ◽

Distribution Functions ◽

Parton Distribution Functions ◽

Electron Positron ◽

Functional Forms ◽

Fixed Order ◽

Logarithmic Accuracy

Abstract The electron, positron, and photon Parton Distribution Functions (PDFs) of the unpolarised electron have recently been computed at the next-to-leading logarithmic accuracy in QED, by adopting the $$ \overline{\mathrm{MS}} $$ MS ¯ factorisation scheme. We present here analogous results, obtained by working in a different framework that is inspired by the so-called DIS scheme. We derive analytical solutions relevant to the large-z region, where we show that the behaviour of the PDFs depends in a dramatic way on whether running-α effects are included to all orders, as opposed to being truncated to some fixed order. By means of suitable initial and evolution conditions, next-to-leading logarithmic accurate PDFs are obtained whose large-z functional forms are identical to those of their leading logarithmic counterparts.