Incoherent diffractive dijet production in electron DIS off nuclei at high energy

Abstract

We study incoherent diffractive dijet production in electron-nucleus deep inelastic scattering at small $x_{\mathrm{Bj}}$ within the Color Glass Condensate. We follow the general approach of [1] but we focus on the correlation limit, that is, when the momentum transfer ${\Delta }_{\perp }$ and the gluon saturation momentum $Q_s$ of the nucleus are much smaller than the individual jet momentum $P_{\perp }$. We arrive at analytic expressions for the dijet cross section, which can be written as a sum of four terms which exhibit factorization: each such term is a product between a hard factor, which includes the decay of the virtual photon to the $q\bar{q}$ pair, and a semi-hard one which involves the dipole-nucleus scattering amplitude. We further calculate the azimuthal anisotropies $⟨\cos 2\varphi ⟩$ and $⟨\cos 4\varphi ⟩$. They are of the same order in the hard momentum $P_{\perp }$, but the $⟨\cos 4\varphi ⟩$ is logarithmically suppressed due to its dependence on the semi-hard factor. Finally, in order to extend the validity of our result towards the perturbative domain, we calculate the first higher kinematic twist, i.e. the correction of relative order ${\Delta }_{\perp }^2/P_{\perp }^2$.

Comments: 31 pages, 9 figures, 4 appendices