Hys.J.C Web page of Perugia matrix element along with the parton
Hys.J.C Web page of Perugia matrix element plus the parton shower the CKKWL matching scheme is applied with a scale parameter which is set to a quarter on the mass of the gluino.The ATLAS A set of tuned parameters (tune) for the underlying event is employed collectively together with the NNPDF.LO parton distribution function (PDF) set.The EvtGen v.system is utilised to describe the properties of the bottom and charm hadron decays within the signal samples.The signal crosssections are calculated at nexttoleading order (NLO) in the sturdy coupling continuous, adding the resummation of soft gluon emission at nexttoleadinglogarithmic accuracy (NLL) .The nominal crosssection and its uncertainty are taken from an envelope of crosssection predictions working with different PDF sets and factorisation and renormalisation scales .The simulated occasion samples for the SM backgrounds are summarised in Table , as well as the PDFs and tunes made use of.Additional samples are also utilised to assess systematic uncertainties, as explained in Sect..For the production of t t and single major quarks within the W t and schannel the powheg box v generator using the CT PDF sets inside the matrixelement calculations is used.Electroweak tchannel singletopquark events are generated utilizing the powheg box v generator.This generator makes use of the fourflavour scheme for the NLO matrixelement calculations together together with the fixed fourflavour PDF set CTf.For all topquark processes, topquark spin correlations are preserved (for the singletop tchannel, leading quarks are decayed employing MadSpin ).The parton shower, fragmentation and the underlying occasion are simulated working with Pythia .with all the CTEQL PDF set and the corresponding Perugia tune (P) .The topquark mass is assumed to become .GeV.The t t events are normalised to the NNLONNLL crosssections.The singletopquark events are normalised for the NLO crosssections.Events containing W or Z bosons with associated jets (W Z jets) are simulated utilizing the Sherpa .generator with APS-2-79 MEK massive bcquarks.Matrix elements are calculated for as much as two partons at NLO and 4 partons at leading order (LO).The matrix elements are calculated utilizing the Comix and OpenLoops generators and merged with all the Sherpa .parton shower employing the MEPS@NLO prescription .The CT PDF set is utilized in conjunction with a committed partonshower tuning created by the Sherpa authors.The WZ jets events are normalised to their NNLO crosssections .The diboson samples are generated using the identical generator and PDF setup as the WZ jets samples described above.The diboson processes are simulated like final states with 4 charged leptons, 3 charged leptons and one particular neutrino, two charged leptons and two neutrinos, and one particular charged lepton and 3 neutrinos.The matrix components include all diagrams with four electroweak vertices.They areSherpa defaultSherpa defaultTuneTable Simulated background occasion samples the corresponding generator, parton shower, crosssection normalisation, PDF set and underlyingevent tune are shownNNPDF.LO Pythia .MG_aMC@NLO .NLONLO CTfACrosssection normalisationPDF setNNLONNLLNNLONNLONLONLO Pythia .powheg box vParton showerPythia .Pythia .Sherpa .Sherpa .Sherpa .powheg box vpowheg box vGeneratorSherpa .Singletop (s and W tchannel) t t WZ W WSingletop (tchannel)) jetsPhysics processW jetsZ ( ttW W , W Z and Z ZSherpa .Sherpa .NLONLO CTNLO CTNLO CTNLO CTNLO CTSherpa defaultPerugiaPerugia Web page ofEur.Phys.J.C calculated for up to one particular parton ( ,) or no PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/21307348 more partons ( ,) at NLO and as much as three parton.
