Non-eikonal corrections to dijet production in DIS

Abstract

We compute non-eikonal corrections to dijet production in deep inelastic scattering off a nucleus. Such corrections are expected to be quantitatively important at the energies of the future Electron Ion Collider. We focus on those corrections stemming solely from the finite longitudinal size of the nucleus. For both longitudinally and transversely polarized photons, we provide general, all-order expressions in terms of two-dimensional path integrals. To proceed further, we use the harmonic oscillator approximation for the target averages of Wilson lines. We then expand the general expressions order by order beyond the shockwave limit which provides the eikonal results, up to next-to-next-to-eikonal accuracy. We observe that next-to-eikonal corrections to this observable vanish for the mentioned approximation for target averages, as previously found for single gluon production in proton-nucleus collisions. Finally, we calculate the back-to-back of correlation limit of our expressions.

Figures (4)

• Figure 1: Diagrams illustrating the process $\gamma^{\ast}_{L,T}+A\to q\bar{q}X$. $k,p$ denote momenta, $x,y,z$ positions and $r,s$ helicities. The modulus of transverse vectors is defined as $x\equiv |{\bm{x}}|$.
• Figure 2: Diagrams illustrating the next-to-eikonal contributions to the amplitude coming from the relaxation of the shockwave approximation. A third diagram identical to Fig. \ref{['Fig:Diagrama2']}, corresponding to splitting after the nucleus, also contributes.
• Figure 3: Separation into regions for the Before-Inside contribution.
• Figure 4: Separation into regions for the Inside-Inside contribution.