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Title: Distinguishing Quarks and Gluons in Pion and Kaon PDFs

Abstract

The leading-twist parton distribution functions of the pion and kwon are calculated for the first time using a rainbow-ladder truncation of QCD's Dyson-Schwinger equations (DSEs) that self-consistently sums all planar diagrams. The nonperturbative gluon dressing of the quarks is thereby correctly accounted for, which in practice means solving the inhomogeneous Bethe-Salpeter equation (BSE) for the quark operator that defines the spin-independent quark distribution functions. An immediate consequence of using this dressed vertex is that gluons carry 35% of the pion's and 30% of the kaon's light-cone momentum, with the remaining momentum carried by the quarks. The scale associated with these DSE results is μ0 = 0.78 GeV. The gluon effects generated by the inhomogeneous BSE are inherently nonperturbative and cannot be mimicked by the perturbative QCD evolution equations. A key consequence of this gluon dressing is that the valence quarks have reduced support at low-to-intermediate x, where the gluons dominate, and increased support at large x. As a result, our DSE calculation of the pion's valence quark distribution is in excellent agreement with the Conway et al. pion-induced Drell-Yan data, but nevertheless exhibits the qπ(x) similar or equal to (1 - x)2 behavior as x -> 1 predicted by perturbativemore » QCD.« less

Authors:
 [1];  [2];  [3]
  1. Argonne National Lab. (ANL), Argonne, IL (United States); Kent State Univ., Kent, OH (United States)
  2. Argonne National Lab. (ANL), Argonne, IL (United States)
  3. Kent State Univ., Kent, OH (United States); Univ. of Adelaide, SA (Australia)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
National Science Foundation (NSF); USDOE Office of Science (SC), Nuclear Physics (NP)
OSTI Identifier:
1607468
Grant/Contract Number:  
AC02-06CH11357
Resource Type:
Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 124; Journal Issue: 4
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Bednar, Kyle D., Cloet, Ian C., and Tandy, Peter C. Distinguishing Quarks and Gluons in Pion and Kaon PDFs. United States: N. p., 2020. Web. https://doi.org/10.1103/PhysRevLett.124.042002.
Bednar, Kyle D., Cloet, Ian C., & Tandy, Peter C. Distinguishing Quarks and Gluons in Pion and Kaon PDFs. United States. https://doi.org/10.1103/PhysRevLett.124.042002
Bednar, Kyle D., Cloet, Ian C., and Tandy, Peter C. Fri . "Distinguishing Quarks and Gluons in Pion and Kaon PDFs". United States. https://doi.org/10.1103/PhysRevLett.124.042002. https://www.osti.gov/servlets/purl/1607468.
@article{osti_1607468,
title = {Distinguishing Quarks and Gluons in Pion and Kaon PDFs},
author = {Bednar, Kyle D. and Cloet, Ian C. and Tandy, Peter C.},
abstractNote = {The leading-twist parton distribution functions of the pion and kwon are calculated for the first time using a rainbow-ladder truncation of QCD's Dyson-Schwinger equations (DSEs) that self-consistently sums all planar diagrams. The nonperturbative gluon dressing of the quarks is thereby correctly accounted for, which in practice means solving the inhomogeneous Bethe-Salpeter equation (BSE) for the quark operator that defines the spin-independent quark distribution functions. An immediate consequence of using this dressed vertex is that gluons carry 35% of the pion's and 30% of the kaon's light-cone momentum, with the remaining momentum carried by the quarks. The scale associated with these DSE results is μ0 = 0.78 GeV. The gluon effects generated by the inhomogeneous BSE are inherently nonperturbative and cannot be mimicked by the perturbative QCD evolution equations. A key consequence of this gluon dressing is that the valence quarks have reduced support at low-to-intermediate x, where the gluons dominate, and increased support at large x. As a result, our DSE calculation of the pion's valence quark distribution is in excellent agreement with the Conway et al. pion-induced Drell-Yan data, but nevertheless exhibits the qπ(x) similar or equal to (1 - x)2 behavior as x -> 1 predicted by perturbative QCD.},
doi = {10.1103/PhysRevLett.124.042002},
journal = {Physical Review Letters},
number = 4,
volume = 124,
place = {United States},
year = {2020},
month = {1}
}

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Works referenced in this record:

Pion Form Factor
journal, July 1979


What Can We Count on? A Discussion of Constituent-Counting Rules for Interactions Involving Composite Systems
journal, December 1982


Pion and kaon valence quark distribution functions from Dyson-Schwinger equations
journal, September 2018


π - and K -meson Bethe-Salpeter amplitudes
journal, December 1997


Interaction model for the gap equation
journal, October 2011


Behavior of Current Divergences under SU 3 × SU 3
journal, November 1968


Wide-angle scattering in softened field theory
journal, September 1974


Explanation and prediction of observables using continuum strong QCD
journal, July 2014


Exclusive processes in perturbative quantum chromodynamics
journal, November 1980


Whirlpools in the Sea: Polarization of Antiquarks in a Spinning Proton
journal, October 1977


Parton distribution functions for twist 4
journal, December 1983


Pion parton distribution function in the valence region
journal, December 2005


Electromagnetic transition form factors of light mesons
journal, April 2002


Factorization of large-x quark distributions in a hadron
journal, March 2005


Basic features of the pion valence-quark distribution function
journal, October 2014


First Monte Carlo Global QCD Analysis of Pion Parton Distributions
journal, October 2018


Asymptotic behavior of the pion form factor in quantum chromodynamics
journal, February 1980

  • Efremov, A. V.; Radyushkin, A. V.
  • Theoretical and Mathematical Physics, Vol. 42, Issue 2
  • DOI: 10.1007/BF01032111

Quark Structure Functions of Mesons and the Drell-Yan Process
journal, April 1979


Generalized parton distributions at x 1
journal, March 2004


Nucleon and pion distribution functions in the valence region
journal, October 2010


Decay of the Pi Meson
journal, June 1958


Generalized parton distributions
journal, December 2003


Measurement of the structure function ratio using the Drell-Yan process
journal, June 1980


Hard exclusive electroproduction of two pions and their resonances
journal, August 1999


The intrinsic gluon component of the nucleon
journal, September 1997


Pion Distribution Amplitude from Lattice QCD
journal, August 2013


Nucleon quark distributions in a covariant quark–diquark model
journal, August 2005


Pion and Nucleon Structure Functions near x = 1
journal, November 1975


Pion and kaon valence-quark parton distribution functions
journal, June 2011


Parton model and the Bethe-Salpeter wave function
journal, February 1977


Pion valence-quark parton distribution function
journal, October 2015


Experimental study of muon pairs produced by 252-GeV pions on tungsten
journal, January 1989

  • Conway, J. S.; Adolphsen, C. E.; Alexander, J. P.
  • Physical Review D, Vol. 39, Issue 1
  • DOI: 10.1103/PhysRevD.39.92

Valence-quark distribution functions in the kaon and pion
journal, April 2016


Imaging Dynamical Chiral-Symmetry Breaking: Pion Wave Function on the Light Front
journal, March 2013


Valence-quark distributions in the pion
journal, January 2001


Exclusive processes in quantum chromodynamics: Evolution equations for hadronic wavefunctions and the form factors of mesons
journal, November 1979


Transversity quark distributions in a covariant quark–diquark model
journal, January 2008


Nucleon quark distribution functions from the Dyson–Schwinger equations
journal, July 2018


Pion Electromagnetic Form Factor at Spacelike Momenta
journal, October 2013


Baryons as relativistic three-quark bound states
journal, November 2016

  • Eichmann, Gernot; Sanchis-Alepuz, Hèlios; Williams, Richard
  • Progress in Particle and Nuclear Physics, Vol. 91
  • DOI: 10.1016/j.ppnp.2016.07.001

Soft-Gluon Resummation and the Valence Parton Distribution Function of the Pion
journal, December 2010


Transverse-momentum-dependent quark distribution functions of spin-one targets: Formalism and covariant calculations
journal, October 2017


Polarized and unpolarized intrinsic gluon distributions
journal, January 1990


π, K + , and K 0 electromagnetic form factors
journal, October 2000


Decay of the Pi Meson
journal, March 1956


Pion distribution amplitude from lattice QCD
journal, May 2017


    Works referencing / citing this record:

    Pion and kaon parton distribution functions from basis light front quantization and QCD evolution
    journal, February 2020