Infrared Renormalons in Kinematic Distributions for Hadron Collider Processes

TL;DR

This paper investigates the presence of linear infrared renormalons in the transverse momentum distribution of Z bosons at hadron colliders using an Abelian model, finding no evidence of such renormalons in high transverse momentum regions.

Contribution

It provides a numerical analysis of linear renormalons in Z boson transverse momentum distributions within a simplified Abelian framework, addressing concerns about soft radiation effects.

Findings

No evidence of linear renormalons in high transverse momentum regions

Renormalon effects are negligible regardless of rapidity cuts

Analysis performed in the large $b_0$ limit

Abstract

Infrared renormalons in Quantum Chromodynamics are associated with non-perturbative corrections to short distance observables. Linear renormalons, i.e. such that the associated non-perturbative corrections scale like one inverse power of the hard scale, can affect at a non-negligible level even the very high-energy phenomena studied at the Large Hadron Collider. Using an Abelian model, we study the presence of linear renormalons in the transverse momentum distribution of a neutral vector boson $Z$ produced in hadronic collisions. We consider a process where the $Z$ transverse momentum is balanced by a sizable recoil against a coloured final state particle. One may worry that such a colour configuration, not being azimuthally symmetric, could generate unbalanced soft radiation, associated in turn with linear infrared renormalons affecting the transverse momentum distribution of the vector boson. We performed a numerical calculation of the renormalon effects for this process in the so-called large $b_0$ limit. We found no evidence of linear renormalons in the transverse momentum distribution of the $Z$ in the large transverse-momentum region, irrespective of rapidity cuts.