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 ${\mathrm{\ensuremath{\Delta}}}_{\ensuremath{\perp}}$ and the gluon saturation momentum ${Q}_{s}$ of the nucleus are much smaller than the individual jet momentum ${P}_{\ensuremath{\perp}}$. 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 $q\overline{q}$ pair, and a semihard one which involves the dipole-nucleus scattering amplitude. We further calculate the azimuthal anisotropies $⟨\mathrm{cos}2\ensuremath{\phi}⟩$ and $⟨\mathrm{cos}4\ensuremath{\phi}⟩$. They are of the same order in the hard momentum ${P}_{\ensuremath{\perp}}$, but the $⟨\mathrm{cos}4\ensuremath{\phi}⟩$ is logarithmically suppressed due to its dependence on the semihard 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 ${\mathrm{\ensuremath{\Delta}}}_{\ensuremath{\perp}}^{2}/{P}_{\ensuremath{\perp}}^{2}$.