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This content will become publicly available on June 13, 2017

Title: Experimental results on TMDs

QCD factorisation for semi-inclusive deep inelastic scattering at low transverse momentum in the current-fragmentation region has been established recently, providing a rigorous basis to study the Transverse Momentum Dependent distribution and fragmentation functions (TMDs) of partons from Semi-Inclusive DIS data using different spin-dependent and spin-independent observables. The main focus of the experiments were the measurements of various single- and double-spin asymmetries in hadron electro-production (ep{up-arrow} --> ehX ) with unpolarised, longitudinally and transversely polarised targets. The joint use of a longitudinally polarised beam and longitudinally and transversely polarised targets allowed to measure double-spin asymmetries (DSA) related to leading-twist distribution functions describing the transverse momentum distribution of longitudinally and transversely polarised quarks in a longitudinally and transversely polarised nucleons (helicity and worm-gear TMDs). Furthermore, the single-spin asymmetries (SSA) measured with transversely polarised targets, provided access to specific leading-twist parton distribution functions: the transversity, the Sivers function and the so-called 'pretzelosity' function. In this review we present the current status and some future measurements of TMDs worldwide.
Authors:
Publication Date:
OSTI Identifier:
1264169
Report Number(s):
JLAB-PHY--16-2225; DOE/OR/23177--3862
Journal ID: ISSN 1434-6001; PII: 518
Grant/Contract Number:
AC05-06OR23177
Type:
Accepted Manuscript
Journal Name:
European Physical Journal. A
Additional Journal Information:
Journal Volume: 52; Journal Issue: 6; Journal ID: ISSN 1434-6001
Publisher:
Springer
Research Org:
Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS