NLO impact factor for inclusive photon$+$dijet production in $e+A$ DIS at small $x$

Abstract

We compute the next-to-leading order (NLO) impact factor for inclusive photon $+$dijet production in electron-nucleus (e+A) deeply inelastic scattering (DIS) at small $x$. An important ingredient in our computation is the simple structure of ``shock wave" fermion and gluon propagators. This allows one to employ standard momentum space Feynman diagram techniques for higher order computations in the Regge limit of fixed $Q^2\gg {\Lambda }_{\mathrm{QCD}}^2$ and $x\to 0$. Our computations in the Color Glass Condensate (CGC) effective field theory include the resummation of all-twist power corrections $Q_s^2/Q^2$, where $Q_s$ is the saturation scale in the nucleus. We discuss the structure of ultraviolet, collinear and soft divergences in the CGC, and extract the leading logs in $x$; the structure of the corresponding rapidity divergences gives a nontrivial first principles derivation of the JIMWLK renormalization group evolution equation for multiparton lightlike Wilson line correlators. Explicit expressions are given for the $x$-independent $O({\alpha }_s)$ contributions that constitute the NLO impact factor. These results, combined with extant results on NLO JIMWLK evolution, provide the ingredients to compute the inclusive photon $+$ dijet cross-section at small $x$ to $O({\alpha }_s^3\ln (x))$. First results for the NLO impact factor in inclusive dijet production are recovered in the soft photon limit. A byproduct of our computation is the LO photon+ 3 jet (quark-antiquark-gluon) cross-section.

104 pages, 35 figures; references added, typo in Eq. 275 corrected

References in corpus (23)

• The Color Glass Condensate
• Universality of Unintegrated Gluon Distributions at small x
• NLO evolution of color dipoles
• Triumvirate of Running Couplings in Small-x Evolution
• Solving The High Energy Evolution Equation Including Running Coupling Corrections
• High energy factorization in nucleus-nucleus collisions
• Photon impact factor in the next-to-leading order
• Non-linear evolution in QCD at high-energy beyond leading order
• Dipole factorization for DIS at NLO: Combining the $q\bar{q}$ and $q\bar{q}g$ contributions
• Color Memory
• High Gluon Densities in Heavy Ions Collisions
• NLO JIMWLK evolution unabridged
• Universality of multi-particle production in QCD at high energies
• Particle production in field theories coupled to strong external sources. II: Generating functions
• Probing gluon saturation with next-to-leading order photon production at central rapidities in proton-nucleus collisions
• Parton model description of multiparticle azimuthal correlations in $pA$ collisions
• The Color Glass Condensate density matrix: Lindblad evolution, entanglement entropy and Wigner functional
• Impact factor for high-energy two and three jets diffractive production
• The Asymptotic Form of Non-Global Logarithms, Black Disc Saturation, and Gluonic Deserts
• NLO evolution of 3-quark Wilson loop operator
• One loop light-cone QCD, effective action for reggeized gluons and QCD RFT calculus
• Improvement for Color Glass Condensate factorization: single hadron production in pA collisions at next-to-leading order
• Pomeron with a running coupling in the nucleus

Cited by in corpus (1)

• HERA data and collinearly-improved BK dynamics