TY - JOUR
T1 - Parton distributions and lattice QCD calculations
T2 - A community white paper
AU - Lin, Huey Wen
AU - Nocera, Emanuele R.
AU - Olness, Fred
AU - Orginos, Kostas
AU - Rojo, Juan
AU - Accardi, Alberto
AU - Alexandrou, Constantia
AU - Bacchetta, Alessandro
AU - Bozzi, Giuseppe
AU - Chen, Jiunn Wei
AU - Collins, Sara
AU - Cooper-Sarkar, Amanda
AU - Constantinou, Martha
AU - Del Debbio, Luigi
AU - Engelhardt, Michael
AU - Green, Jeremy
AU - Gupta, Rajan
AU - Harland-Lang, Lucian A.
AU - Ishikawa, Tomomi
AU - Kusina, Aleksander
AU - Liu, Keh Fei
AU - Liuti, Simonetta
AU - Monahan, Christopher
AU - Nadolsky, Pavel
AU - Qiu, Jian Wei
AU - Schienbein, Ingo
AU - Schierholz, Gerrit
AU - Thorne, Robert S.
AU - Vogelsang, Werner
AU - Wittig, Hartmut
AU - Yuan, C. P.
AU - Zanotti, James
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2018/5
Y1 - 2018/5
N2 - In the framework of quantum chromodynamics (QCD), parton distribution functions (PDFs) quantify how the momentum and spin of a hadron are divided among its quark and gluon constituents. Two main approaches exist to determine PDFs. The first approach, based on QCD factorization theorems, realizes a QCD analysis of a suitable set of hard-scattering measurements, often using a variety of hadronic observables. The second approach, based on first-principle operator definitions of PDFs, uses lattice QCD to compute directly some PDF-related quantities, such as their moments. Motivated by recent progress in both approaches, in this document we present an overview of lattice-QCD and global-analysis techniques used to determine unpolarized and polarized proton PDFs and their moments. We provide benchmark numbers to validate present and future lattice-QCD calculations and we illustrate how they could be used to reduce the PDF uncertainties in current unpolarized and polarized global analyses. This document represents a first step towards establishing a common language between the two communities, to foster dialogue and to further improve our knowledge of PDFs.
AB - In the framework of quantum chromodynamics (QCD), parton distribution functions (PDFs) quantify how the momentum and spin of a hadron are divided among its quark and gluon constituents. Two main approaches exist to determine PDFs. The first approach, based on QCD factorization theorems, realizes a QCD analysis of a suitable set of hard-scattering measurements, often using a variety of hadronic observables. The second approach, based on first-principle operator definitions of PDFs, uses lattice QCD to compute directly some PDF-related quantities, such as their moments. Motivated by recent progress in both approaches, in this document we present an overview of lattice-QCD and global-analysis techniques used to determine unpolarized and polarized proton PDFs and their moments. We provide benchmark numbers to validate present and future lattice-QCD calculations and we illustrate how they could be used to reduce the PDF uncertainties in current unpolarized and polarized global analyses. This document represents a first step towards establishing a common language between the two communities, to foster dialogue and to further improve our knowledge of PDFs.
KW - Global QCD fits
KW - Lattice QCD
KW - Unpolarized/polarized parton distribution functions (PDFs)
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U2 - 10.1016/j.ppnp.2018.01.007
DO - 10.1016/j.ppnp.2018.01.007
M3 - Review article
AN - SCOPUS:85042027801
SN - 0146-6410
VL - 100
SP - 107
EP - 160
JO - Progress in Particle and Nuclear Physics
JF - Progress in Particle and Nuclear Physics
ER -