S -channel single top quark production and decay at next-to-next-to-leading-order in QCD

Ze Long Liu,Jun Gao

doi:10.1103/physrevd.98.071501

Abstract

We report on a fully differential next-to-next-to-leading order (NNLO) calculation of s-channel single top (anti-)quark production with a semi-leptonic decay at the LHC, neglecting the color correlation between the light and heavy quark lines and in the narrow width approximation. The NNLO corrections can increase the cross section by about 10% in the low transverse momentum region of the top quark and reduce scale variation uncertainty. In order to compare with experimental results without unfolding procedures, we also present theoretical predictions with fiducial cuts, including total cross sections and distributions of observables used in the experimental multivariate analysis. The NNLO corrections are found to be about -8% for fiducial cross sections.

Highlights

In the standard model (SM) of particle physics, the top quark is the heaviest elementary particle
By considering next-to-next-to-leading order (NNLO) corrections, the inclusive cross sections are enhanced by about 7% in general
The increase of cross sections at low transverse momentum of the top quark can reach above 10%

Summary

INTRODUCTION

In the standard model (SM) of particle physics, the top quark is the heaviest elementary particle. It is sensitive to new resonances such as W0 or charged Higgs bosons involved in various models beyond the standard model (BSM) physics [4,5] It serves as an important background process to Higgs studies and BSM searches [6,7,8,9]. S-channel single top quark production was first observed by the D0 Collaboration in 2013 [10], and it was confirmed in the combined analysis by the D0 and CDF Collaborations [11] at the Fermilab Tevatron It was measured by the ATLAS and CMS Collaborations at the LHC with 7 and 8 TeV data [12,13]. We present a next-to-next-to-leading order (NNLO) QCD calculation of s-channel single top (anti) quark production and decay at the LHC using the phase space slicing method.

METHOD

NUMERICAL RESULTS

CONCLUSIONS