Jet production in (un)polarized pp collisions: dependence on jet algorithm

TL;DR

This paper studies how different jet algorithms affect high-pT jet production and spin asymmetries in polarized proton collisions at RHIC, providing analytical results and comparing cone- and kt-type algorithms.

Contribution

It extends analytical NLO calculations for jet cross sections in polarized pp collisions, analyzing the impact of jet algorithms on observables.

Findings

Jet cross sections vary significantly with the jet algorithm used.

Spin asymmetries are relatively insensitive to the choice of jet algorithm.

Analytical NLO results are accurate across a wide energy range.

Abstract

We investigate single-inclusive high-pT jet production in longitudinally polarized pp collisions at RHIC, with particular focus on the algorithm adopted to define the jets. Following and extending earlier work in the literature, we treat the jets in the approximation that they are rather narrow, in which case analytical results for the corresponding next-to-leading order partonic cross sections can be obtained. This approximation is demonstrated to be very accurate for practically all relevant situations, even at Tevatron and LHC energies. We confront results for cross sections and spin-asymmetries based on using cone- and kt-type jet algorithms. We find that jet cross sections at RHIC can differ significantly depending on the algorithm chosen, but that the spin asymmetries are rather robust. Our results are also useful for matching threshold-resummed calculations of jet cross sections to fixed-order ones.