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VBFNLO: A parton level Monte Carlo for processes with electroweak bosons -- Manual for Version 2.7.0

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 Added by Michael Rauch
 Publication date 2011
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and research's language is English




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VBFNLO is a flexible parton level Monte Carlo program for the simulation of vector boson fusion (VBF), QCD induced single and double vector boson production plus two jets, and double and triple vector boson production (plus jet) in hadronic collisions at next-to-leading order (NLO) in the strong coupling constant, as well as Higgs boson plus two jet production via gluon fusion at the one-loop level. For the new version -- Version 2.7.0 -- several major enhancements have been included into VBFNLO. The following new production processes have been added: $Wgamma jj$ in VBF, $HHjj$ in VBF, $W$, $Wj$, $WH$, $WHj$, $ppto text{Spin-2}jj$ in VBF (with $text{Spin-2}to WW/ZZtotext{leptons}$) and the QCD induced processes $WZjj$, $Wgamma jj$, $W^pm W^pm jj$ and $Wjj$ production. The implementation of anomalous gauge boson couplings has been extended to all triboson and VBF $VVjj$ processes, with an enlarged set of operators yielding anomalous couplings. Finally, semileptonic decay modes of the vector bosons are now available for many processes, including $VVjj$ in VBF, $VVV$ and $VVgamma$ production.



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138 - K. Arnold , M. Bahr , G. Bozzi 2009
VBFNLO is a fully flexible parton level Monte Carlo program for the simulation of vector boson fusion, double and triple vector boson production in hadronic collisions at next-to-leading order in the strong coupling constant. VBFNLO includes Higgs and vector boson decays with full spin correlations and all off-shell effects. In addition, VBFNLO implements CP-even and CP-odd Higgs boson via gluon fusion, associated with two jets, at the leading-order one-loop level with the full top- and bottom-quark mass dependence in a generic two-Higgs-doublet model. A variety of effects arising from beyond the Standard Model physics are implemented for selected processes. This includes anomalous couplings of Higgs and vector bosons and a Warped Higgsless extra dimension model. The program offers the possibility to generate Les Houches Accord event files for all processes available at leading order.
VBFNLO is a flexible parton level Monte Carlo program for the simulation of vector boson fusion (VBF), double and triple vector boson (plus jet) production as well as QCD-induced single and double vector boson production plus two jets in hadronic collisions at next-to-leading order (NLO) in the strong coupling constant. Furthermore, Higgs boson plus two jet production via gluon fusion at the one-loop level is included. This note briefly describes the main additional features and processes that have been added in the new release -- VBFNLO Version 2.7.0. At NLO QCD several new processes are available. These are $W^pmgamma$ and $HH$ production in VBF, the QCD-induced single and double vector boson plus two jets processes $W^pm jj$, $W^pm Zjj$, $W^pmgamma jj$, same-sign $W^pm W^pm jj$, and the Higgs-strahlung process $W^pm H$ (plus jet) production. Anomalous couplings are now available for all VBF, diboson and triboson (plus jet) processes including the new VBF $W^pmgamma jj$ implementation, as well as in the Higgs-strahlung (plus jet) process. Semi-leptonic decay modes are supported for the following diboson, triboson and VBF processes: $VV$, $VVV$, $VVgamma$ production and $VV$ production via VBF, where $V$ denotes a massive gauge boson, i.e. $W^pm$ or $Z$. Additionally, the VBF-Higgs production process with decay into $WW$ or $ZZ$ supports semi-leptonic decays of the gauge bosons. All these semi-leptonic processes contain the possibility to include anomalous gauge boson couplings.
We present a comprehensive new global QCD analysis of polarized inclusive deep-inelastic scattering, including the latest high-precision data on longitudinal and transverse polarization asymmetries from Jefferson Lab and elsewhere. The analysis is performed using a new iterative Monte Carlo fitting technique which generates stable fits to polarized parton distribution functions (PDFs) with statistically rigorous uncertainties. Inclusion of the Jefferson Lab data leads to a reduction in the PDF errors for the valence and sea quarks, as well as in the gluon polarization uncertainty at $x gtrsim 0.1$. The study also provides the first determination of the flavor-separated twist-3 PDFs and the $d_2$ moment of the nucleon within a global PDF analysis.
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