Precision DIS thrust predictions for HERA and EIC

Abstract

We present predictions for the DIS 1-jettiness event shape $\ddot{I}{„}_1^b$, or DIS thrust, using the framework of Soft Collinear Effective Theory (SCET) for factorization, resummation of large logarithms, and rigorous treatment of nonperturbative power corrections, matched to fixed-order QCD away from the resummation region. Our predictions reach next-to-next-to-next-to-leading-logarithmic (N${}^3$LL) accuracy in resummed perturbation theory, matched to $O(\hat{I}{\pm }_s^2)$ fixed-order QCD calculations obtained using the program NLOJet++. We include a rigorous treatment of hadronization corrections, which are universal across different event shapes and kinematic variables $x$ and $Q$ at leading power, and supplement them with a systematic scheme to remove $O(\hat{I}{›}_{\text{QCD}})$ renormalon ambiguities in their definition. The framework of SCET allows us to connect smoothly the nonperturbative, resummation, and fixed-order regions, whose relative importance varies with $x$ and $Q$, and to rigorously estimate theoretical uncertainties, across a broad range of $x$ and $Q$ covering existing experimental results from HERA as well as expected new measurements from the upcoming Electron-Ion-Collider (EIC). Our predictions will serve as an important benchmark for the EIC program, enabling the precise determination of the QCD strong coupling $\hat{I}{\pm }_s$ and the universal nonperturbative first moment parameter $\hat{I}{\text{c◯}}_1$.

65 pages, 27 figures, published version