ar X iv : h ep - p h / 02 02 14 2 v 1 1 5 Fe b 20 02 Polarized Virtual Photon Structure Function g γ 2 and Twist - 3 Effects in QCD
نویسندگان
چکیده
We investigate the twist-3 effects in the polarized virtual photon structure. The structure functions g 1 and g γ 2 of polarized photon could be experimentally studied in the future polarized ep or ee colliders. The leading contributions to g 1 are the twist-2 effects, while another structure function g 2 , which only exists for the virtual photon target, receives not only the twist-2 but also twist-3 contributions. We first show that the twist-3 effects actually exist in the box-diagram contributions and we extract the twist-3 part, which can also be reproduced by the pure QED operator product expansion. We then calculate the non-trivial lowest moment (n = 3) of the twist-3 contribution to g 2 in QCD. For large Nc (the number of colors), the QCD analysis of the twist-3 effects in the flavor nonsinglet part of g 2 becomes tractable and we can obtain its moments in a compact form for all n. YNU-HEPTh-02-101 KUCP-201 February 2002 e-mail address: [email protected] e-mail address: [email protected] e-mail address: [email protected]
منابع مشابه
ar X iv : h ep - p h / 02 02 14 2 v 2 1 8 A pr 2 00 2 Polarized Virtual Photon Structure Function g γ 2 and Twist - 3 Effects in QCD
We investigate the twist-3 effects in the polarized virtual photon structure. The structure functions g 1 and g γ 2 of polarized photon could be experimentally studied in the future polarized ep or ee colliders. The leading contributions to g 1 are the twist-2 effects, while another structure function g 2 , which only exists for the virtual photon target, receives not only the twist-2 but also ...
متن کاملar X iv : h ep - p h / 02 11 13 0 v 1 9 N ov 2 00 2 1 Twist - 3 effects for polarized virtual photon structure function
We investigate twist-3 effects in the polarized virtual photon. The structure function g γ 2 , which exists only for the virtual photon target and can be measured in future polarized e + e − collider experiments, receives both twist-2 and twist-3 contributions. The twist-3 part is analyzed in pure QED interaction as well as in LO QCD. We find the twist-3 contribution is appreciable for the phot...
متن کاملar X iv : h ep - p h / 01 02 29 6 v 1 2 3 Fe b 20 01 Twist - 3 in Proton Nucleon Single Spin Asymmetries
The generation of the single spin asymmetries by the twist 3 effects in QCD is discussed. While the short-distance subprocesses is calculable in the Born approximation, some properties of large distance partonic correlations may be extracted by means of sum rules relating them to the DIS spin structure function g 2. The simple model for twist 3 part of the latter is proposed. The numerical anal...
متن کاملar X iv : h ep - p h / 02 07 37 1 v 1 3 1 Ju l 2 00 2 HIGHER TWISTS AND NUCLEAR EFFECTS
We discuss the impact of nuclear effects on the higher twist terms using a particular example of the structure function xF 3 as extracted from a QCD fit to neutrino deep inelastic data on a heavy nucleus target.
متن کامل