Monte-Carlo event generation for CEPC Xin Mo Institute of High Energy Physics Nov. 20, 2015 Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Outline Introduction of CEPC generation work 250GeV 350GeV NLO plans Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Basic information Sample information: CM energy: 250GeV Luminosity: 5000fb-1 Polarization: unpolarized ISR: on Beamstrahlung: off Generator Matrix element: Whizard1.95 Shower & hadronization: Pythia6.4 Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Workflow Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Stdhep Root Marlin Whizard, Pythia Geant4, Mokka Stdhep Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Physics Signal part (Higgs) SM Background 2 fermions 4 fermions 6 fermions(350GeV) Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Higgs signal Higgs-strahlung Vector boson fusion Monte-Carlo event generation for the CEPC

Classification of 4 fermions WW type Mixing type ZZ type Single W type Single mixing type Single Z type Monte-Carlo event generation for the CEPC

Workshop on Monti-Carlo for CEPC CFHEP Cuts Default cuts Applied on the invariant mass of colored or charged particle pairs, on the energy of emitted photons or gluons, and on the momentum transfer to exchanged photons or gluons. M ≥10GeV Workshop on Monti-Carlo for CEPC CFHEP

Monte-Carlo event generation for the CEPC Summary table Cross sections [fb] 240GeV 250GeV qq 54662 50216 μ+μ- 4685 4405 single Z 4538 4734 single W 5086 5144 W+W- 16004 15484 ZZ 1079 1033 ZH 203 212 W fusion 5.36 6.72 Z fusion 0.50 0.63 Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Number of events Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC 350GeV sample Sample information e+e-  ZH; SM backgrounds; ttbar; 350GeV; 1000fb-1; ISR on; format: stdhep Topology Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC 6fermions ttbar consisting of down type quarks and two virtual W bosons tt_dtdtutdtutdt, tt_dtdtutdtlv, tt_dtdtlvlv ZWW consisting of one virtual Z(excluding down types) and two virtual W bosons named with prefix zww, 9 sub-processes ZZZ consisting of three virtual Z bosons(excluding up-down pairs) named with prefix zzz, 12 sub-processes Monte-Carlo event generation for the CEPC

Cross sections(6fermions) Process σ(fb-1) tt_dtdtlvlv 11.656 tt_dtdtutdtlv 45.566 tt_dtdtutdtutdt 43.106 zww 10-1~1 zzz ~10-2 Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC NLO process Leading order: Omega Next-to-Leading order: Openloops Radiation Vertex correction Loop correction Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC NLO event generation Openloops Matching Whizard Powheg Loop calculation HepMC LHEF Pythia8 Hadronize Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Cross sections 250GeV ISR & beamstrahlung NLO LO uu 11121 10760 dd 10227 9829 cc 11068 10459 ss 10100 9902 bb 10237 9822 LO vs NLO Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Validation Monte-Carlo truth level Fast simulation Full simulation Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Summary Mass production 250GeV signal and SM backgrounds 350GeV 6fermions backgrounds NLO Beginning for NLO study Validation and cross check Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Thanks Thanks for attention! Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Backup Backup Monte-Carlo event generation for the CEPC

Monte-Carlo event generation for the CEPC Interfaces OpenLoops for one-loop calculation; QCD correction Powheg for shower matching stdhep, lcio, lhe outputs Monte-Carlo event generation for the CEPC