Asymmetric jet correlations in p p^\uparrow scattering
Daniel Boer, Werner Vogelsang
TL;DR
The paper tackles how to probe transverse-spin phenomena through single-spin asymmetries in hadronic collisions by proposing back-to-back jet production in $p p^{\uparrow}$ as a leading-power observable sensitive to the Sivers function, including the gluon component. It develops a framework based on transverse-momentum dependent distributions and Wilson-line induced Sivers effects, incorporating Sudakov suppression in a simplified, phenomenological way. The authors estimate the asymmetry for RHIC at jet $p_T \sim 10$ GeV with and without Sudakov effects, finding that the asymmetry can reach the percent level and provide access to the gluon Sivers function. Their approach connects to existing STAR measurements of back-to-back correlations and offers a practical observable to test nonvalence Sivers contributions in QCD.
Abstract
We propose that back-to-back correlations in azimuthal angle of jets produced in collisions of unpolarized with transversely polarized proton beams could be used to determine Sivers functions. The corresponding single-spin asymmetry is not power-suppressed, but is subject to Sudakov suppression. We present estimates of the asymmetry (without and with Sudakov effects) for RHIC at jet transverse momenta of ~10 GeV and show that it may reach a few per cent or more and could provide access to the gluon Sivers function.