Twist-4 photon helicity-flip amplitude in DVCS on a nucleon in the Wandzura-Wilczek approximation

Authors
Kivel, N Mankiewicz, L
Citation
N. Kivel et L. Mankiewicz, Twist-4 photon helicity-flip amplitude in DVCS on a nucleon in the Wandzura-Wilczek approximation, EUR PHY J C, 21(4), 2001, pp. 621-629
Citations number
37
Categorie Soggetti
Physics
Journal title
EUROPEAN PHYSICAL JOURNAL C
ISSN journal
14346044 → ACNP
Volume
21
Issue
4
Year of publication
2001
Pages
621 - 629
Database
ISI
SICI code
1434-6044(200107)21:4<621:TPHAID>2.0.ZU;2-4
Abstract
We computed the twist-4 part of the photon spin-flip amplitude in deeply vi rtual Compton scattering on a nucleon in the Wandzura-Wilczek approximation , We found a factorizable contribution, which arises from photon scattering on quarks with non-zero angular momentum along the collision axis. As the genuine twist-2 amplitude arises at the NLO, for moderate virtualities of t he hard photon, Q(2) less than or equal to 10 GeV2, a kinematical twist-4 c orrection can give a numerically important contribution to the photon helic ity-flip amplitude.