We explore the complete cross-section for the production of unpolarized hadrons in semi-inclusive deep-inelastic scattering up to power-suppressed O(1/Q2) terms in the Wandzura-Wilczek-type (WW-type) approximation, which consists in systematically assuming that q¯gq-correlators are much smaller than q¯q-correlators. Under the applicability of WW-type approximations, certain relations among transverse momentum dependent parton distribution functions (TMDs) and fragmentation functions (FFs) occur which are used to approximate SIDIS cross-section in terms of a smaller subset of TMDs and FFs. We discuss the applicability of the WW-type approximations on the basis of available data.
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Semi-Inclusive Deep Inelastic Scattering in Wandzura-Wilczek-type approximation
We present the complete cross-section for the production of unpolarized hadrons in semi-inclusive deep-inelastic scattering up to power-suppressed O(1/Q^2) terms in the Wandzura-Wilczek-type approximation, which consists in systematically assuming that qgqbar-terms are much smaller than qqbar -correlators. We compute all twist-2 and twist-3 structure functions and the corresponding asymmetries, and discuss the applicability of the Wandzura-Wilczek-type approximations on the basis of available data. We make predictions that can be tested by data from COMPASS, HERMES, Jefferson Lab, and the future Electron-Ion Collider. The results of this paper can be readily used for phenomenology and for event generators, and will help to improve the description of semi-inclusive deep-inelastic processes in terms of transverse momentum dependent parton distribution functions and fragmentation functions beyond the leading twist.
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- Award ID(s):
- 1812423
- NSF-PAR ID:
- 10104062
- Date Published:
- Journal Name:
- The journal of high energy physics
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/JHEP06(2019)007
