Transverse momentum resummation for t -channel single top quark production at the LHC

We present a next-to-leading order accurate simulation of t-channel single-top plus jet production matched to parton showers via the Powheg method. The calculation underlying the simulation is enhanced with a process-specific implementation of the multi-scale improved NLO (Minlo) method, such that it gives physical predictions all through phase space, including regions where the jet additional to the t-channel single-top process is unresolved. We further describe a tuning procedure for the Minlo Sudakov form factor, fitting the coefficient of the first subleading term in its exponent using an artificial neural-network. The latter tuning, implemented as a straightforward event-byevent reweighting, renders the Minlo simulation NLO accurate for t-channel single-top observables, in addition to those of the analogous single-top plus jet process.

Section: Jhep09(2018)108mentioning

confidence: 99%

MINLO t-channel single-top plus jet

Carrazza

Frederix

Zanderighi

et al. 2018

“…[46,47] and ref. [48], respectively. Monte Carlo simulations, in which the NLO single-top production processes have been matched to a parton shower are available in the MC@NLO [45,[49][50][51][52], Sherpa [53] and POWHEG [51,54,55] frameworks.…”

Section: Introductionmentioning

confidence: 97%

Precise predictions for single-top production: the impact of EW corrections and QCD shower on the t-channel signature

Frederix

Pagani

Tsinikos

2019

In this work we calculate and provide precise predictions for the signature that is typically exploited at the LHC for the measurement of t-channel single-top production: 1 lepton, 1 light jet, 1 b-jet, / E T and no additional jets or leptons. We apply the cuts that define the fiducial region and we take into account all the contributions to this signature; not only those from resonant t-channel single-top production. On the one hand, we calculate the complete-NLO corrections, i.e., all NLO effects of QCD and EW origin. On the other hand, we study in detail the impact of a QCD parton shower for the fiducial region we consider. We provide predictions in different approximations at the inclusive level and for several differential distributions. Our study demonstrates the relevance of both EW corrections and shower effects for obtaining precise and reliable theoretical predictions for the single-top-production fiducial region.

“…Soft gluon resummation is considered in refs. [52][53][54][55][56][57][58]. Matching NLO calculations to parton shower is done in the framework of POWHEG and MC@NLO [49,[59][60][61].…”

Section: Introductionmentioning

confidence: 99%

Top-quark mass determination from t-channel single top production at the LHC

Gao

Yuan

Gao

2021

We study the determination of the top-quark mass using leptonic observables in t-channel single top-quark production at the LHC. We demonstrate sensitivity of transverse momentum of the charged lepton on the input top-quark mass. We present predictions at next-to-next-to-leading order (NNLO) in QCD with narrow width approximation and structure function approach. Further corrections due to parton shower and hadronization, non-resonant and non-factorized contributions are discussed. To reduce impact of SM backgrounds we propose to use the charge weighted distribution for the measurement, i.e., differences between distributions of charged lepton with positive and negative charges. By modeling both signal and background processes, we found the projections for (HL-)LHC to be promising, with a total theoretical uncertainty on the extracted top-quark mass of about 1 ∼ 2 GeV.