Polarized Deep Inelastic and Elastic Scattering From Gauge/String Duality

Abstract

In this paper, we investigate deep inelastic and elastic scattering on a polarized spin-1/2 hadron using gauge/string duality. This spin-1/2 hadron corresponds to a supergravity mode of the dilatino. The polarized deep inelastic structure functions are computed in supergravity approximation at large t' Hooft coupling $\lambda$ and finite $x$ with ${\lambda }^{-1/2}\ll x<1$. Furthermore, we discuss the moments of all structure functions, and propose an interesting sum rule ${\int }_0^1\text{d}x{g}_2(x,q^2)=0$ for $g_2$ structure function which is known as the Burkhardt-Cottingham sum rule in QCD. In the end, the elastic scattering is studied and elastic form factors of the spin-1/2 hadron are calculated within the same framework.

Comments: 21 pages, 3 figues.v2:fixed a few typos, ref added. v3: more typos fixed, context edited, ref updated; v4: comments added, 1 more figure added