Level 3 Muon Data

• Martin Wegner's introductory note on the muon trigger:
  Note.
  
• Jon Hays' introduction to l3fanalyze:
  Note.
  
• The original design note (very old).
  
• The old L3 Muon page.
  
• The section on muon index/muon quality at the end of this page.
  

How to obtain the L3 trigger information

Or you write your own framework-executable. In this case you may find the following following chapter interesting.
(Note: To compare reco and L3 information, in almost all cases you will have to make a framework executable. While including MC information in the trigsim ntuple is fairly straightforward, including reco information is not and there are no plans to change this.)

Physics and Debug Info

Getting L3 information from DST-chunks

In general

In our case the chunks you need are the classes L3Chunk for the physics and L3DebugChunk for the debug info, both belonging to the package l3fchunk

The idea of both, the debug and the physics chunk, is generally that they contain a std::map which assignes a keyword to an instance of the class that contains the data for a certain tool. To make things easy, the keyword is the toolname which you can find in your toollist (or the trigger list), e.g. "MUO_LOCAL".

In the case of L3DebugChunk the mentioned class is derived from L3DebugInfo (package l3utilites), in the case of L3Chunk it's derived from L3PhysicsResults (package l3fresults). In order to get these maps from the chunk you can use the methods L3DebugChunk::getDebugInfo() or L3Chunk::getPhysToolMap() resp.

In detail

How to practically realize the access to the variables is probably explained best by examples:
(The relevant methods and classes are highlighted. For a complete list of all accessors please have a look at the source code of the respective classes

• Code example how to extract information about segments in the local muon system from L3TMuoLocalDebugInfo *localinfo:

  const Muon::SegmentCollection& muoseg = localinfo->getSegmentCollection();   // vector of segments -- package muo_segment
  for(Muon::SegmentCollection::const_iterator seg=muoseg.begin();
      seg!=muoseg.end();
      seg++){
         cout << "Phi = " << seg->phi() << endl;                               // Example: retrieve phi angle
  }
      

• Code example how to extract information about tracks in the local muon system from L3TMuoLocalDebugInfo *localinfo:

  const std::vector<Muon::Track>& muotrack = localinfo->getLocalTrackVector(); // vector of tracks -- package muo_trackreco
  for(std::vector<Muon::Track>::const_iterator track=muotrack.begin();
      track!=muotrack.end();
      track++){
         cout << "Theta = " << track->getTheta() << endl;                      // Example: retrieve theta angle
  }
  

• Code example how to extract information about local muons matched to central tracks from L3TMuoCentralMatchDebugInfo *cminfo:

  const std::vector<L3MuoTrack> l3muotrackvec = cminfo->getL3MuoTrackVector(); // vector of L3 muon tracks -- package l3fmuo_local
  for (std::vector<L3MuoTrack>::const_iterator l3track=l3muotrackvec.begin(); 
       l3track!=l3muotrackvec.end();
       l3track++) {
          L3MuoCentralMatchData matchdata = (*l3track).getCentralMatchData();  // This class contains the relevant information about the central match
          cout << "Central pT = " << matchdata.pt_central << endl;             // no accessors here - just public class members.
  }
  

• Code example how to extract information about raw hits from L3TMuoUnpackDebugInfo *unpinfo:
  (This is slightly more complicated...)

  const Muon::PDTHitCollection &pdtcollection = unpinfo->getMuoHitCollection().getPDTHits();    // vector of PDT hits -- package muo_hit  
  const Muon::MDTHitCollection &mdtcollection = unpinfo->getMuoHitCollection().getMDTHits();    // vector of MDT hits -- package muo_hit
  const Muon::MSCHitCollection &msccollection = unpinfo->getMuoHitCollection().getMSCHits();    // vector of MSC hits -- package muo_hit
  // Loop over the MSC hits (for MDT and PDT alalogous)
  for (Muon::MSCHitCollection::const_iterator it_scint=msccollection.begin();
      it_scint != msccollection.end();
      it_scint++){
  
    // ---- First get the detector information ---
    Muon::MuoIndex index = it_scint->getMuoIndex();                            // MuoIndex: Collection of deector information
    cout << "Phi = " << index.phi() << endl;                                   // Example: retrieve phi angle
   
    // ---- Now get the information about geometrical hit positions ---
    Muon::MSCGeometryHit pdthitadaptor((Muon::MSCHit*)it_scint);
    const SpacePoint& point = mschitadaptor.getGlobalPosition();
    cout << "x = " << point.x() << "  y = " << point.y() << "  z = " << point.z() << endl;
     }
  

Getting L3 information from the root tuple

A few hints for TrigSimAnalyze

To select offline/online chunks (if the default option is not what you want) change trigsim_analyze/rcp/runTrigSimAnalyze_l3only.rcp:

    RCP l3fana =<l3fanalyze L3Analyze_auto_online>

    RCP l3fana =<l3fanalyze L3Analyze_auto_offline>

Naming conventions

• Up to version p15.06.01 the branch name is the same as the tool name as defined in the toollist file ("toollist.txt" by default).
• Up to version p15.06.01 the leaf name is composed like

    <TOOLNAME>_[p/d]_[on/off]_<VARIABLENAME>,

  where
  • <TOOLNAME> is identical to the branch name
  • p or d stands for "physics" or "debug" chunk resp.
  • on or off stands fo "online" or "offline"
  • <VARIABLENAME> is the variable name as found in the table below.

• As of version p15.07.00 the branch name is composed like

    L3<3-LETTER-IDENTIFIER>[D/PR],

  where PR or D stands for "physics" or "debug" chunk resp. For the 3-letter identifier see documentation.
• As of version p15.07.00 the leaf name is composed like

    <ABBREV-TOOLNAME>_<NUMBER>_[on/off]_<VARIABLENAME>, 

  where ABBREV-TOOLNAME is an abbreviation of the tool's class name (i.e "L3MuoLocal"). The number is a consecutive 2-digit number. (For details see documentation.)

Summary of the ROOT Tuple content

ROOT-branch MUOUNPACK_DEFAULT

ROOT-branch MUO_LOCAL

ROOT branch Muon_p

Type	Name	Description
Int_t	n	Number of entries
Float_t	ET	Transverse energy (or momentum)
Float_t	Eta	(Detector) eta
Float_t	kineT
Float_t	kineX
Float_t	kineY
Float_t	kineZ
Float_t	vtxX	x-coordinate of the vertex
Float_t	vtxY	y-coordinate of the vertex
Float_t	vtxZ	z-coordinate of the vertex

The second group of variables is specific to the muon physics results.

Type	Name	Description
Int_t	NMUON	Number of entries
Float_t	MUONregion	Region of the muon track (-1=South, 0=Central, 1=North)
Float_t	MUONoctant	Octant of the muon track
Float_t	MUONeta	Eta of the local muon track
Float_t	MUONphi	Phi of the local muon track
Float_t	MUONxA	x-coordinate of the segment in the A-layer
Float_t	MUONyA	y-coordinate of the segment in the A-layer
Float_t	MUONzA	z-coordinate of the segment in the A-layer
Float_t	MUONxB	x-coordinate of the segment in the BC-layer
Float_t	MUONyB	y-coordinate of the segment in the BC-layer
Float_t	MUONzB	z-coordinate of the segment in the BC-layer
Float_t	MUONquality	See note below
Float_t	MUONetrack	Energy of the muon track in the calorimeter (not yet used)
Float_t	MUONhfrac	Hadronic fraction of the muon track in the calorimeter (not yet used)
Float_t	MUONimpactXY	Impact parameter of the central track
Float_t	MUONsignifImpactXY	Significance of the impact parameter
Float_t	MUONcmEta	Eta of the matching central track
Float_t	MUONcmPhi	Phi of the matching central track
Float_t	MUONcmZ	Z-position of the matching central track
Float_t	MUONcmPt	Transverse momentum of the matching central track
Float_t	MUONchisq	Chi^2 of the central match

L3MuoCalMatchDebugInfoExaminer: Any volunteers to write some documentation ?

L3MuoCentralMatchDebugInfoExaminer: Due to its stupidly long variable names it crashes the analyze program (hence the new naming scheme). If you are running a p15 version with the old naming scheme and you aren't interested in it's results, take it out of the tool list. If you need it, p15.07 should work, otherwise go in the examiner (l3fanalyze/L3MuoCentralMatchDebugInfoExaminer.cpp) and rename the variables ('NCentralmatch' ?!) to something a bit shorter and recompile.

More random notes on the content

Momenta

    float pT_local = 
    abs((*iter)->getMomentA().perp()/(*iter)->getMomentA().mag(),*(*iter)->getMomentum());
    

to reproduce the equivalent number from the l3fanalyze ntuple use: TRKpxb, TRKpyb and TRKpzb

Muon Quality:

Muon Index

region:	0 = central, 1 = north, 2 = south
type:	0 = wire chamber, 1 = scintillator
layer:	0 = A-layer, 1 = B-layer, 2 = C-layer
octant:	0-7, 0 starts at x-axis towards y-axis
barrel:	(central only) A: 1, 2, 3; B/C: 0, 1, 2, 3, 4; B/C octants 5, 6: 0, 1, 3, 4 (These numbers are also encoded in the PDTs: PDT = ijk, where i = layer, j = barrel, k = octant)
plane:	scintillators: 0, Wires: increasing away from the origin Wire A-layer: 0, 1, 2, 3; Central A-layer, Octants 5 \ 6: 0, 1, 2 Wire B/C-layer: 0, 1, 2
eta:	Central: increases in z, Forward: increases in r
phi:	Wire: 0, Scint: 0-9, increases in global phi. Note that the labeling in phi is not symmetric around the beam.
tube:	Scintillator with 2 PMT: 0-1, MDT: 0-7