CMSSW TutorialCMSSW TutorialA. NikitenkoA. Nikitenko

• IntroductionIntroduction

• Example of reconstruction: “how to”Example of reconstruction: “how to”

• Running CMSSW with ASAPRunning CMSSW with ASAP

• Home work useful for tau id groupHome work useful for tau id group

IntroductionIntroduction

Event processing: “physics” viewEvent processing: “physics” view

• Event generation (in MC world) Event generation (in MC world)

• Digitization Digitization

• Local reconstructionLocal reconstruction

• High level object reconstructionHigh level object reconstruction

• Event selectionEvent selection

• Event analysisEvent analysis

Event processing: CMSSW viewEvent processing: CMSSW view

• Event processing is a sequence of modulesEvent processing is a sequence of modules• Type of CMSSW modules:Type of CMSSW modules:

– Source Source • Event generator: PYTHIA, HERWIG, …Event generator: PYTHIA, HERWIG, …• File containing some data for further processingFile containing some data for further processing

– MC infoMC info

– DigiDigi

– ……....

– EDProducerEDProducer– EDFilterEDFilter– OutputModuleOutputModule– EDAnalyzerEDAnalyzer

Event processing: CMSSW viewEvent processing: CMSSW view

Important to know one of the CMSSW rules:Important to know one of the CMSSW rules: object produced in one module can not be object produced in one module can not be updated/modified in other moduleupdated/modified in other module

How to run itHow to run it

• Command Command

cmsRun –p name.cfgcmsRun –p name.cfg

run event processingrun event processing• User file User file

name.cfg name.cfg

define modules that user want to run and define modules that user want to run and sequence of running (path)sequence of running (path)

• .cfg file is .cfg file is configuration fileconfiguration file which uses which uses CMS CMS program configuration languageprogram configuration language

https://uimon.cern.ch/twiki/bin/view/CMS/ConfigurationFileUsage

Example: Example: gen + sim-digi-reco in one step + analysisgen + sim-digi-reco in one step + analysis

• Full example can be found onFull example can be found on http://cmsdoc.cern.ch/~anikiten/cms-higgs/CMSSW/allRecohttp://cmsdoc.cern.ch/~anikiten/cms-higgs/CMSSW/allReco

• I will show you now only few elementsI will show you now only few elements– Jet reconstructionJet reconstruction– Analysis (access to information) with Analysis (access to information) with

“Framework analyser”.“Framework analyser”.

Code fragments shown on the next slides are taken from allReco.cfg Code fragments shown on the next slides are taken from allReco.cfg

Source module (or POOL Source)Source module (or POOL Source)

• I have generated already some events I have generated already some events (di-taus, back-to-back) and store them (di-taus, back-to-back) and store them into into mcpool.rootmcpool.root file. This file is file. This file is “source module” for further event “source module” for further event processingprocessing

Standard name

Module creating “raw” Calo TowersModule creating “raw” Calo Towers

Module name; user defines it.

Name of c++ class in CMSSW who produces Calo towers

Code above could be put into .cfi file and this file can be included in .cfg as:

module caloTowers = CaloTowerCandidateCreator { string src = towerMaker” double minimumEt = 0.5 double minimumE = 0.8}

Module creating Calo Towers Module creating Calo Towers used for jet finderused for jet finder

Module name; user defines it.

Name of c++ class in CMSSW who produces Calo Towers used by jet finder

Name of the module who produced “raw” Calo Towers; see previous slide

Module creating jetsModule creating jets

Module name; user defines it.

Name of c++ class in CMSSW who produces Calo Towers used by jet finder

Name of the module who produced Calo Towers to be used by jet finder; see previous slide

Output ModuleOutput Module

Standard nameUser name to beused later

User name of output filenames of modules producedobjects user does not want to be stored into output file

Event processing steps: pathEvent processing steps: path

• Few modules can be combined as Few modules can be combined as sequencesequence

• Modules and sequences define Modules and sequences define pathpath: : sequence of processing stepssequence of processing steps

output module name

Analysis of output root fileAnalysis of output root file

• bare root - no CMSSW libs neededbare root - no CMSSW libs needed

• FWlite mode - few CMSSW libs neededFWlite mode - few CMSSW libs needed

• Analysis in a Framework analyzerAnalysis in a Framework analyzer– cmsRun –p name.cfgcmsRun –p name.cfg

• name.cfg is user configuration file to run analysis name.cfg is user configuration file to run analysis • analysis uses full CMSSW frameworkanalysis uses full CMSSW framework

See on the next slides example of full Framework analysis See on the next slides example of full Framework analysis

analysis.cfganalysis.cfg

user name

Name of c++ class performing analysis’user access info and fill/store histos there

modules which produced objects inprevious step to be analyzed now

Output filefrom previousstep

Access event data in Analyzer Access event data in Analyzer (Analyzer.cc)(Analyzer.cc)

Running CMSSW with GRID/ASAPRunning CMSSW with GRID/ASAP

• Instructions can be found onInstructions can be found on http://cmsdoc.cern.ch/~anikiten/cms-higgs/ASAP_CMSSW_jobhttp://cmsdoc.cern.ch/~anikiten/cms-higgs/ASAP_CMSSW_job

• Many thanks to ASAP teamMany thanks to ASAP team– Julia AndreevaJulia Andreeva– Olga KodolovaOlga Kodolova– Craig MunroCraig Munro– Juha HerralaJuha Herrala

Homework useful for tau id groupHomework useful for tau id group

• Compare two ways to suppress Compare two ways to suppress electron contamination to tau-jet :electron contamination to tau-jet :– cut on hottest HCAL tower Ecut on hottest HCAL tower ETT in jet in jet

– cut on Ecut on ETTjetjet(hadr)/p(hadr)/pTT

ltrltr

• Using instructions Using instructions

(see page 7) (see page 7)

analyze single e analyze single e

and tau-jet of and tau-jet of

ppTT = 30-60 GeV, = 30-60 GeV,

< 2.2< 2.2.