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12 papers found.
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The NNLO QCD soft function for 1-jettiness

We calculate the soft function for the global event variable 1-jettiness at next-to-next-to-leading order (NNLO) in QCD. We focus specifically on the non-Abelian contribution, which, unlike the Abelian part, is not determined by the next-to-leading order result. The calculation uses the known general forms for the emission of one and two soft partons and is performed using a...

Zγ production at NNLO including anomalous couplings

In this paper we present a next-to-next-to-leading order (NNLO) QCD calculation of the processes pp → l + l −γ and \( pp\to \nu \overline{\nu}\gamma \) that we have implemented in MCFM. Our calculation includes QCD corrections at NNLO both for the Standard Model (SM) and additionally in the presence of Zγγ and ZZγ anomalous couplings. We compare our implementation, obtained using...

Higher order QCD predictions for associated Higgs production with anomalous couplings to gauge bosons

We present predictions for the associated production of a Higgs boson at NLO+PS accuracy, including the effect of anomalous interactions between the Higgs and gauge bosons. We present our results in different frameworks, one in which the interaction vertex between the Higgs boson and Standard Model W and Z bosons is parameterized in terms of general Lorentz structures, and one in...

Predictions for diphoton production at the LHC through NNLO in QCD

In this paper we present a next-to-next-to-leading order (NNLO) calculation of the process pp → γγ that we have implemented into the parton level Monte Carlo code MCFM. We do not find agreement with the previous calculation of this process in the literature. In addition to the \( \mathcal{O}\left({\alpha}_s^2\right) \) corrections present at NNLO, we include some effects arising...

Associated production of a Higgs boson at NNLO

In this paper we present a Next-to-Next-to Leading Order (NNLO) calculation of the production of a Higgs boson in association with a massive vector boson. We include the decays of the unstable Higgs and vector bosons, resulting in a fully flexible parton-level Monte Carlo implementation. We also include all \( \mathcal{O}\left({\alpha}_s^2\right) \) contributions that occur in...

Bounding the Higgs width at the LHC using full analytic results for gg → e − e + μ − μ +

We revisit the hadronic production of the four-lepton final state, e − e + μ − μ + , through the fusion of initial state gluons. This process is mediated by loops of quarks and we provide first full analytic results for helicity amplitudes that account for both the effects of the quark mass in the loop and off-shell vector bosons. The analytic results have been implemented in the...

The matrix element method at next-to-leading order

John M. Campbell 0 Walter T. Giele 0 Ciaran Williams 0 0 Fermilab, Batavia, IL 60510, U.S.A This paper presents an extension of the matrix element method to next-toleading order in perturbation

Next-to-leading order predictions for Zγ + jet and Zγγ final states at the LHC

We present next-to-leading order predictions for final states containing leptons produced through the decay of a Z boson in association with either a photon and a jet, or a pair of photons. The effect of photon radiation from the final state leptons is included and we also allow for contributions arising from fragmentation processes. Phenomenological studies are presented for the...

Gluon-gluon contributions to W + W − production and Higgs interference effects

In this paper we complete our re-assessment of the production of W boson pairs at the LHC, by calculating analytic results for the \( gg \to {W^{+} }{W^{-} } \to \nu {l^{+} }{l^{-} }\bar{\nu } \) process including the effect of massive quarks circulating in the loop. Together with the one-loop amplitudes containing the first two generations of massless quarks propagating in the...

Vector boson pair production at the LHC

John M. Campbell 0 R. Keith Ellis 0 Ciaran Williams 0 0 Fermilab, Batavia, IL 60510, U.S.A We present phenomenological results for vector boson pair production at the LHC, obtained using the

NLO Higgs boson production plus one and two jets using the POWHEG BOX, MadGraph4 and MCFM

We present a next-to-leading order calculation of Higgs boson production plus one and two jets via gluon fusion interfaced to shower Monte Carlo programs, implemented according to the POWHEG method. For this implementation we have used a new interface of the POWHEG BOX with MadGraph4, that generates the codes for generic Born and real processes automatically. The virtual...

One-loop Higgs plus four gluon amplitudes: full analytic results

We consider one-loop amplitudes of a Higgs boson coupled to gluons in the limit of a large top quark mass. We treat the Higgs as the real part of a complex field ϕ that couples to the self-dual field strengths and compute the one-loop corrections to the ϕ-NMHV amplitude, which contains one gluon of positive helicity whilst the remaining three have negative helicity. We use four...