# New definition of TMD parton densities

@inproceedings{Collins2011NewDO, title={New definition of TMD parton densities}, author={John C. Collins}, year={2011} }

I give an account of a new definition of transverse-momentum-dependent parton densities. The new definition solves a number of difficulties and inconsistencies in earlier definitions.

#### 46 Citations

Relating transverse structure of various parton distributions

- Physics
- 2015

A bstractWe present the results of T-even TMDs in a light front quark-diquark model of nucleons with the wave functions constructed from the soft-wall AdS/QCD prediction. The relations amongst TMDs… Expand

Key Features of the TMD Soft-Factor Structure

- Physics
- 2014

We show that the geometry of the Wilson lines, entering the operator definition of the transverse-momentum dependent parton distributions and that of the soft factor, follows from the kinematics of… Expand

Geometry of gauge links in operator definitions of transverse-momentum dependent PDFs: A comparative view

- Physics
- 2011

Different approaches to the problem of a gauge-invariant operator definition of transverse-momentum dependent parton densities (TMDs) are reviewed and compared from the point of view of their… Expand

Transverse-momentum-dependent parton distributions at the edge of the lightcone

- Physics
- 2011

We present a completely gauge-invariant operator definition of transverse-momentum-dependent parton densities (TMD), supplied with longitudinal lightlike gauge links as well as transverse gauge links… Expand

Overview of TMD evolution

- Physics
- 2016

Transverse momentum dependent parton distributions (TMDs) appear in many scattering processes at high energy, from the semi-inclusive DIS experiments at a few GeV to the Higgs transverse momentum… Expand

Studying the gluon TMDs with J/ψ- and Upsilon- pair production at the LHC

- Physics
- Proceedings of XXVII International Workshop on Deep-Inelastic Scattering and Related Subjects — PoS(DIS2019)
- 2019

We report on how J/ψ- and Υ-pair production are promising processes to access the polarised and unpolarised gluon TMDs at the LHC. We present the formalism used, as well as resulting observables that… Expand

Non-dipolar gauge links for transverse-momentum-dependent pion wave functions

- Physics
- 2016

I discuss the factorization-compatible definitions of transverse-momentumdependent (TMD) pion wave functions which are fundamental theory inputs entering QCD factorization formulae for many hard… Expand

Transverse momentum in double parton scattering: factorisation, evolution and matching

- Physics
- 2017

A bstractWe give a description of double parton scattering with measured transverse momenta in the final state, extending the formalism for factorisation and resummation developed by Collins, Soper… Expand

A note on Pretzelosity TMD parton distribution

- Physics
- Physics Letters B
- 2019

Abstract We show that the transverse-momentum-dependent parton distribution, called as Pretzelosity function, is zero at any order in perturbation theory of QCD for a single massless quark state.… Expand

Wilson Lines off the Light-Cone in TMD PDFs

- Physics
- 2014

Transverse momentum dependent (TMD) parton distribution functions also take into account the transverse momentum (pT) of the partons. The pT-integrated analogues can be linked directly to quark and… Expand

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