Diffractive dijet photoproduction at the EIC

Abstract

We present a first, detailed study of diffractive dijet photoproduction at the recently approved electron-ion collider (EIC) at BNL. Apart from establishing the kinematic reaches for various beam types, energies and kinematic cuts, we make precise predictions at next-to-leading order (NLO) of QCD in the most important kinematic variables. We show that the EIC will provide new and more precise information on the diffractive parton density functions (PDFs) in the pomeron than previously obtained at HERA, illuminate the still disputed mechanism of global vs. only resolved-photon factorization breaking, and provide access to a completely new quantity, i.e. nuclear diffractive PDFs.

Snowmass 2021 White Paper: Electron Ion Collider for High Energy Physics

“…It is expected that information from jet production at an EIC will complement inclusive DIS measurements, similarly to the case at HERA where it was useful in reducing uncertainties in gluon PDFs [325]. Moreover, dijet production at the EIC will offer a unique opportunity to determine the polarized PDFs of the photon [322], and diffractive PDFs [326].…”

Prospects for diffractive dijet photoproduction at the EIC

“…From experience at HERA, the (asymmetric) cuts on the transverse momenta p T 1,(2) can be as low as 5 (4.5) GeV [15]. The K-factor of NLO/LO cross sections is about two for an anti-k T jet radius of R = 1 except at the kinematic edges, where it can be larger [16]. T of the contribution from gluons in the pomeron.…”

Selected topics in diffraction with protons and nuclei: past, present, and future

“…Diffractive dijet photoproduction in ep and eA scattering in the EIC kinematics using next-to-leading order (NLO) of QCD was considered in Ref. [83]. The analysis established the kinematic reaches in most important kinematic variables for various beam types, energies and kinematic cuts.…”

“…Similarly, one can study diffractive dijet photoproduction in lepton-proton and lepton-nucleus scattering at the future Electron-Ion Collider (EIC) in the US. Using the same framework of NLO pQCD, the cross section for the reaction e + A → e + 2 jets + X + A can be written as follows [83]…”

“…Using the formalism outlined above, one can make predictions for diffractive dijet photoproduction in the EIC kinematics as a function of the jet average transverse momentum pT , the observed longitudinal momentum fractions x obs γ and z obs IP , the proton longitudinal momentum transfer x IP , and the jet pseudorapidity difference ∆η [83]. Given experience from HERA, one can define jets with the anti-k T algorithm with the distance parameter R = 1 and assume that the detectors can identify jets above relatively low transverse energies of p T 1 > 5 GeV (leading jet) and p T 2 > 4.5 GeV (subleading jet).…”