uhussain / LightZPrimeAnalysis

Dark Photon Analysis and LightZPrimeAnalysis

Yang Bai and collaborators have a model in which there exists a light Z', which only has enough mass to decay to a small number of hadrons, perhaps, even a single pair of oppositely charged light hadrons (pi+/-, K+/-). However, it is produced with an additional dark matter candidate. For moderate masses (1 < MZprime < 10 GeV), we get very low multiplicity "pencil" jets. The process to study is:

p p -> Z', DM, DMBar -> u, uBar, MET -> "pencil jet", MET

LightZPrimeGenerator package contains a simple python file to convert LHE files from MadGraph to CMSSW GEN formatted output. Note that this does not do simulation step.

The first analyzer LightZPrimeGenAnalyzer makes an nTuple with information from the generator level for testing.

The second analyzer JetAnalyzer makes simple calculations of the energy weighted eta-, phi- width of jets and also varaibles to do the analysis

Instructions:

cd $CMSSW_BASE/src
cmsenv
git clone https://github.com/uhussain/LightZPrimeAnalysis.git
cd $CMSSW_BASE/src/LightZPrimeAnalysis/LightZPrimeGenerator/test
cmsRun LightZPrimeDecayAndHadronizer.py
cd $CMSSW_BASE/src/LightZPrimeAnalysis/LightZPrimeAnalyzer/test
cmsRun testLightZPrimeGenAnalyzer.py
cd $CMSSW_BASE/src/LightZPrimeAnalysis/JetAnalyzer/test
cmsRun testJetAnalyzer.py

Instructions (in order to apply all recommended MET Filters):

cmsrel CMSSW_8_0_18_patch1
cmsenv
git cms-init
git cms-merge-topic -u cms-met:CMSSW_8_0_X-METFilterUpdate
git clone -b darphoton https://github.com/gomber/LightZPrimeAnalysis.git
scram b
cd CMSSW_8_0_18_patch1/src/LightZPrimeAnalysis/JetAnalyzer/test
cmsRun testJetAnalyzer.py

https://twiki.cern.ch/twiki/bin/viewauth/CMS/MissingETOptionalFiltersRun2#Details about the application of the filters: