Nucleon Tomography with 0-jettiness

TL;DR

This paper introduces a new method using 0-jettiness to better isolate the nucleon's 3D structure in TMD observables, significantly improving the measurement of spin asymmetries in boson production.

Contribution

It presents a novel approach employing 0-jettiness to suppress initial-state radiation, enhancing the detection of nucleon spin asymmetries in collider experiments.

Findings

Enhanced asymmetry signals by up to 83% at $q_\perp$=5 GeV

Demonstrated improved testability of the Sivers function sign change

Applicable to measurements at RHIC and Electron-Ion Collider

Abstract

We propose a novel strategy to systematically isolate the nucleon's intrinsic non-perturbative three-dimensional structure by employing 0-jettiness to suppress initial-state radiation in transverse momentum-dependent (TMD) observables. Applying this method to transverse single spin asymmetries (SSAs) in W+/- and Z0 boson production at RHIC, we demonstrate a substantial enhancement of the asymmetry signal (e.g., by 83% for Z0 SSA at $q_\perp$=5 GeV), enabling a more definitive test of the predicted sign change of the Sivers function -- a key prediction of TMD factorization. We further explore its applicability to spin-dependent measurements at the Electron-Ion Collider. Our analysis is formulated within a joint resummation framework that systematically resums large logarithms associated with both the veto scale and the gauge boson's transverse momentum.