Understanding the large-distance behavior of transverse-momentum-dependent parton densities and the Collins-Soper evolution kernel

Abstract

There is considerable controversy about the size and importance of nonperturbative contributions to the evolution of transverse-momentum-dependent (TMD) parton distribution functions. Standard fits to relatively high-energy Drell-Yan data give evolution that when taken to lower Q is too rapid to be consistent with recent data in semi-inclusive deeply inelastic scattering. Some authors provide very different forms for TMD evolution, even arguing that nonperturbative contributions at large transverse distance b_T are not needed or are irrelevant. Here, we systematically analyze the issues, both perturbative and nonperturbative. We make a motivated proposal for the parameterization of the nonperturbative part of the TMD evolution kernel that could give consistency: with the variety of apparently conflicting data, with theoretical perturbative calculations where they are applicable, and with general theoretical nonperturbative constraints on correlation functions at large distances. We propose and use a scheme- and scale-independent function A(b_T) that gives a tool to compare and diagnose different proposals for TMD evolution. We also advocate for phenomenological studies of A(b_T) as a probe of TMD evolution. The results are important generally for applications of TMD factorization. In particular, they are important to making predictions for proposed polarized Drell-Yan experiments to measure the Sivers function.

Misprint and stylistic corrections to correspond to published version

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• Transverse momentum resummation effects in W^+W^- measurements
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Cited by in corpus (47)

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• Resummation of Transverse Momentum Distributions in Distribution Space
• Determination of the Collins-Soper Kernel from Lattice QCD
• Connecting Different TMD Factorization Formalisms in QCD
• Extraction of the Sivers function from SIDIS, Drell-Yan, and $W^{\pm }/Z$ boson production data with TMD evolution
• PDF bias and flavor dependence in TMD distributions
• Flavor dependence of unpolarized quark Transverse Momentum Distributions from a global fit
• N${}^3$LO extraction of the Sivers function from SIDIS, Drell-Yan, and $W^{\pm }/Z$ data
• Updated QCD global analysis of single transverse-spin asymmetries I: Extracting $\tilde{H}$, and the role of the Soffer bound and lattice QCD
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• Disentangling Long and Short Distances in Momentum-Space TMDs
• Tomography of pions and protons via transverse momentum dependent distributions
• Transverse $\Lambda$ Polarization in $e^{+}{e}^{-}$ collisions
• Nonperturbative Collins-Soper Kernel from Chiral Quarks with Physical Masses
• Transverse Momentum Dependent Fragmentation Functions from recent BELLE data
• Drell-Yan Transverse-Momentum Spectra at N${}^3$LL${}^{\prime }$ and Approximate N${}^4$LL with SCETlib
• Several Topics on Transverse Momentum-Dependent Fragmentation Functions
• Combining nonperturbative transverse momentum dependence with TMD evolution
• QCD resummation of dijet azimuthal decorrelations in pp and pA collisions
• Energy-Energy Correlator for jet production in $pp$ and $pA$ collisions
• Determination of the strong-coupling constant from the $Z$-boson transverse-momentum distribution
• Transverse $\Lambda$ polarization in $e^{+}{e}^{-}$ processes within a TMD factorization approach and the polarizing fragmentation function
• Towards three-dimensional nucleon structures at the Electron-Ion Collider in China: A study of the Sivers function
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• The resolution to the problem of consistent large transverse momentum in TMDs
• Basics of factorization in a scalar Yukawa field theory
• Precision three-dimensional imaging of nuclei using recoil-free jets
• Double parton distributions out of bounds in colour space
• QCD and Hadron Physics
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• QCD predictions for the azimuthal asymmetry in charm leptoproduction for the COMPASS kinematics
• Rapidity evolution of TMDs with running coupling
• Transformation of transverse momentum distributions from Parton Branching to Collins-Soper-Sterman framework
• $\sin ({\varphi }_{\Lambda }-{\varphi }_S)$ azimuthal asymmetry in transversely polarized $\Lambda$ production in SIDIS within TMD factorization at EIC
• Azimuthal decorrelation for photon induced dijet production in ultra-peripheral collisions of heavy ions
• Tomography of the Rho meson in the QCD Instanton Vacuum: Transverse Momentum Dependent Parton Distribution Functions
• The $\sin 2{\varphi }_h$ azimuthal asymmetry of pion production in SIDIS within TMD factorization
• Extracting the $\Lambda$ Polarizing Fragmentation Function from Belle $e^{+}{e}^{-}$ Data Within the TMD Formalism
• Collins-Soper kernel from lattice QCD at the physical pion mass
• Transverse spin polarization as a novel probe of medium-induced transverse-momentum-broadening effect
• Parton model description of quark and antiquark correlators and TMDs
• Tomography of Pions and Kaons in the QCD Vacuum: Transverse Momentum Dependent Parton Distribution Functions
• Nucleon Tomography with 0-jettiness