The Sivers asymmetry of vector meson production in semi-inclusive deep inelastic scattering

TL;DR

This paper calculates the Sivers asymmetry for vector meson production in semi-inclusive deep inelastic scattering using extracted Sivers functions, confirming their universality and highlighting the potential of future collider data to refine these functions.

Contribution

It performs the first calculation of the Sivers asymmetry for vector mesons using TMD factorization and existing Sivers functions, testing their universality and predicting future collider outcomes.

Findings

Results agree with COMPASS data confirming Sivers function universality.

Different global analyses yield similar fits but diverge in predictions for future colliders.

Future electron-ion collider data can constrain Sivers functions further.

Abstract

The transverse single-spin asymmetry for $\rho^0$ production in semi-inclusive deep inelastic scattering was recently reported by the COMPASS Collaboration. Using the Sivers functions extracted from pion and kaon productions, we perform a calculation of the Sivers asymmetry within the transverse momentum dependent factorization. Our results are consistent with the COMPASS data, confirming the universality of the Sivers functions within current experimental uncertainties. While various global analyses of Sivers functions can equally well describe the current data, we obtain very different predictions on the Sivers asymmetry of $\rho$ and $K^*$ productions at electron-ion colliders, which therefore are expected to provide further constraints.