Introduction

There is a central prediction of the RandallSundrum (RS) model which is the TeV Kaluza-Klein gravitions. They lead to distinct spin-2 resonances spaced according to the roots of the first Bessel function. KK Gravitons are not stable, favour decays to quarks and gluons. KK Graviton has been chosen as benchmark for the exotics di-b-jets analysis, which looks for local excesses in the invariant mass distribution of b-tagged jets.

MC15 13 TeV

sample preparation

• KK Graviton bb for mass values from 1.25TeV to 7TeV.
• Generator: Pythia8 EvtGen
• PDF: NNPDF23LO A14
• JobOption:
  
  

include( "MC15JobOptions/Pythia8_A14_NNPDF23LO_EvtGen_Common.py")
genSeq.Pythia8.Commands += [
"ExtraDimentionsG*:gg2G* = on",
"ExtraDimentionsG*:ffbar2G* = on",
"5100039:m0 = 1500", #set Graviton mass [GeV]
"5100030:onMode = off", # switch off all Graviton decays
"5100039:onIfAny = 5", #switch on Graviton->bb decay
"ExtraDimensionsG*:kappaMG = 1.084", # set kappaMG value
"5100039:mMin = 50.",
"PhaseSpace:mHatMin = 200.",
]

genSeq.Pythia8.UserModes += ["GravFlat:EnergyMode = 13"]

cross section

validation plots

Pick up Graviton 1.5TeV, 2TeV, 5TeV samples

• Graviton mass
  
• pT of leading and subleading jets
• Eta of leading and subleading jets
• yStar and cos(theta*) of leading and subleading jets

MC requests

• Requesting Graviton mass 600, 800, 1000, 1250, 1500, 1750, 2000, 2500, 3000, 3500, 4000, 4500, 5000, 6000, 7000 GeV
• 20k events for masses from 600 to 3000 GeV
• 50k events for masses from 3500 to 7000 GeV

-- BinbinDong - 2018-09-19