Precision direct photon and W-boson spectra at high p_T and comparison to LHC data

TL;DR

This paper presents a high-precision calculation of vector boson and photon spectra at high transverse momentum, incorporating advanced resummation techniques, and demonstrates excellent agreement with LHC data.

Contribution

It introduces a novel application of Soft-Collinear Effective Theory for resummation in vector boson production, improving theoretical accuracy and reducing uncertainties.

Findings

Excellent agreement with ATLAS data on photon and W production

Resummation reduces theoretical uncertainties

Natural scale choices improve calculation stability

Abstract

The differential p_T spectrum for vector boson production is computed at next-to-leading fixed order and including the resummation of threshold logarithms at next-to-next-to-leading logarithmic accuracy. A comparison is made to ATLAS data on direct photon and W production at high transverse momentum p_T, finding excellent agreement. The resummation is achieved by factorizing contributions associated with different scales using Soft-Collinear Effective Theory. Each part is then calculated perturbatively and the individual contributions are combined using renormalization group methods. A key advantage of the effective theory framework is that it indicates a set of natural scale choices, in contrast to the fixed-order calculation. Resummation of logarithms of ratios of these scales leads to better agreement with data and reduced theoretical uncertainties.