TY  - JOUR
A1  - Lindert, J. M.
A1  - Pozzorini, S.
A1  - Boughezal, R.
A1  - Campbell, J. M.
A1  - Denner, A.
A1  - Dittmaier, S.
A1  - Gehrmann-De Ridder, A.
A1  - Gehrmann, T.
A1  - Glover, N.
A1  - Huss, A.
A1  - Kallweit, S.
A1  - Maierhöfer, P.
A1  - Mangano, M. L.
A1  - Morgan, T. A.
A1  - Mück, A.
A1  - Petriello, F.
A1  - Salam, G. P.
A1  - Schönherr, M.
A1  - Williams, C.
T1  - Precise predictions for \(V+\)jets dark matter backgrounds
JF  - European Physical Journal C
N2  - High-energy jets recoiling against missing transverse energy (MET) are powerful probes of dark matter at the LHC. Searches based on large MET signatures require a precise control of the \({Z(ν\overline{ν})}+\) jet background in the signal region. This can be achieved by taking accurate data in control regions dominated by \(Z(ℓ^+ℓ^−)+\) jet, \(W(ℓν)+\) jet and \(γ+\) jet production, and extrapolating to the \({Z(ν\overline{ν})}+\) jet background by means of precise theoretical predictions. In this context, recent advances in perturbative calculations open the door to significant sensitivity improvements in dark matter searches. In this spirit, we present a combination of state-of-the-art calculations for all relevant \(V+\) jets processes, including throughout NNLO QCD corrections and NLO electroweak corrections supplemented by Sudakov logarithms at two loops. Predictions at parton level are provided together with detailed recommendations for their usage in experimental analyses based on the reweighting of Monte Carlo samples. Particular attention is devoted to the estimate of theoretical uncertainties in the framework of dark matter searches, where subtle aspects such as correlations across different \(V+\) jet processes play a key role. The anticipated theoretical uncertainty in the \({Z(ν\overline{ν})}+\) jet background is at the few percent level up to the TeV range.
KW  - Physics
KW  - High energy physics
KW  - High-energy jets
KW  - Dark matter
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172555
VL  - 77
ER  - 
TY  - JOUR
A1  - Biedermann, Benedikt
A1  - Bräuer, Stephan
A1  - Denner, Ansgar
A1  - Pellen, Mathieu
A1  - Schumann, Steffen
A1  - Thompson, Jennifer M.
T1  - Automation of NLO QCD and EW corrections with SHERPA and RECOLA
JF  - European Physical Journal C
N2  - This publication presents the combination of the one-loop matrix-element generator Recola with the multipurpose Monte Carlo program Sherpa. Since both programs are highly automated, the resulting Sherpa +Recola framework allows for the computation of – in principle – any Standard Model process at both NLO QCD and EW accuracy. To illustrate this, three representative LHC processes have been computed at NLO QCD and EW: vector-boson production in association with jets, off-shell Z-boson pair production, and the production of a top-quark pair in association with a Higgs boson. In addition to fixed-order computations, when considering QCD corrections, all functionalities of Sherpa, i.e. particle decays, QCD parton showers, hadronisation, underlying events, etc. can be used in combination with Recola. This is demonstrated by the merging and matching of one-loop QCD matrix elements for Drell–Yan production in association with jets to the parton shower. The implementation is fully automatised, thus making it a perfect tool for both experimentalists and theorists who want to use state-of-the-art predictions at NLO accuracy.
KW  - RECOLA
KW  - SHERPA
KW  - NLO QCD
KW  - EW
KW  - Higgs boson
KW  - Large Hadron Collider
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170615
VL  - 77
IS  - 492
ER  -