Basic D Data Analysis Tutorial

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Basic DØ Data Analysis Tutorial
Frédéric Déliot CEA-Saclay
Vancouver Workshop 13 June 2005
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This Tutorial

• Basic informations about

• DØ releases and data model
• SAM
• DØ data pass and data tiers
• Which release to use for analysis ?
• DØ framework, packages and RCP

• Some How To

• compile and run a DØ executable
• produce a common analysis format root-tree
• compute luminosity

Other tutorials during the Workshop
Tuesday 4PM Trigsim and Rate Tool Tutorial (B.
Vachon, S. Lammers) Thursday 4PM Common
Analysis Format (CAF) Tutorial (R. Hauser)
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How DØ Reconstructed Data Looks Like ?

• DØ Event Data Model (EDM)

• representation of events in memory
• the smallest unit of an event is a chunk
  (zebra bank)
• an event a list of chunks from different types
  (JetChunk, MuonParticleChunk, L3TriggerChunk,
  HistoryChunk )
• a chunk 1 object (MissingET) or a list of
  objects (vector of Jet, vector of MuonParticle, )

• thumbnail

• packed summary of the reconstruction program
  ouput
• (micro-DST)
• ThumbnailChunk (all infos about objects, packed
  format for JetChunk MuonParticleChunk, )
• TMBTriggerChunk (L3 trigger informations)
• HistoryChunk (event processing history),
• will have to unpack it (recreate JetChunk,
  MuonParticleChunk, from ThumbnailChunk) before
  using it

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How DØ Reconstructed Data Can/Will Also Looks
Like ?

• CAF

• common analysis root-based format
• just finished to be developed
• derived from thumbnails

See Reiners tutorial for how to use it
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DØ Data Pass and Data Tiers (for data ? p17)
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Fixing / Skimming / Certifying

• Fixing

• to fix/correct/apply new calibration (mainly for
  calorimeter)
• using thumbnail, on the full dataset, create
  fixed thumbnail
• not a full reconstruction
• in the past pass1 and pass2 on p14 data
• in the future hadronic calibration on p17 data

• Skimming

• isolate interesting events, exclusive
• on thumbnail, create (smaller) skimmed
  thumbnails
• physical skims (files) logical skims (tags in
  the event)

• Certification

• apply standard corrections/cuts developed by the
  ID groups to define good objects suitable for
  most of analyses (Good EM, jets, muon, JES
  corrections, )
• on thumbnail before your analysis
  code/root-tuple maker
• call for d0correct

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Where are the data ?In SAM !

• What is SAM ?

• Sequential data Access via Metadata
• DØ (and CDF) data handling system
• store and retrieve files (from cache disks or
  tapes) using metadata

• What is a SAM metadata ?

• description of a file stored in SAM
• some informations in the metadata are used for
  SAM query

• What is a SAM dataset ?

• an abstract definition of your data
  specification of metadata that will be translated
  into a list of files
• need to use a dataset to run an executable on
  files in SAM

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DØ Releases

• What is release ?

• a complete set of DØ software organized in CVS
  packages
• CVS is the DØ code management system
• development release (new software) tXX.YY.ZZ
  t05.06.00
• production release (official processing)
  pXX.YY.ZZ p17.03.03

• How to setup a release ?

• setup D0RunII pXX.YY.ZZ (non optimal build)
• setup D0RunII pXX.YY.ZZ O SRT_QUALmaxopt
  (optimal build)
• using of not shared libraries
• gmake all (no shared libraries)
• gmake all LINK_SHARED yes (shared libraries
  created)

• Where are the releases located ?

• in /d0dist/dist/releases

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DØ Packages

• What is package ?

• a group of closely related C classes
• specific versions managed by CVS
• standard structure header files directory,
  source files directory, run parameters directory

• RCPs

• run control parameter files text files with
  parameters to control what the package will do
• RCPs stored in a database

• main framework RCP

• RCP of the package executable that controls what
  the executable should do when it is launched
• the string Packages line the list of action
  to do for each event
• RCP alias ltPackageName PackageRCPgt

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DØ Luminosity

• Luminosity basics

• the smallest unit of time for luminosity is the
  luminosity block (LBN luminosity block number),
  60 s
• status assigned to each LBN based on the DAQ
  status (good/bad)
• only data from good LBN can be properly
  normalized

• luminosity access

• luminosity infos are provided only for a
  specific (set of) trigger(s)
• for analysis, usually need the reconstructed
  luminosity

• needed inputs to compute luminosity

• list of files you process
• list of raw data parent files (from SAM)
• your specific list of bad Run and bad LBN (that
  will be added to the DAQ bad list)
• you have to cut out the corresponding bad LBN in
  your analysis code