Bug in AliMUONHit constructor for fPz and fPx calculation (Arthur, Bruce and Ivana)

[u/mrichter/AliRoot.git] / MUON / README

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/* $Id$ */

==========================================================
Please add  to this README file all information concerning 
config files, simulation, digitalization, clusterization, 
reconstruction and macro analysis

==========================================================
 How to run a MUON generation
==========================================================
aliroot
root [0] gAlice->Run(10,"$ALICE_ROOT/MUON/Config_MUON_test.C");

1 single muon of 7 GeV/c in the MUON spectrometer 
acceptance will be simulated using geant3. 
Hit information will be store in the root file in the
execution directory.
If you want to change the option or to define a new directory
for hits, you have to do the following before:
root [0] gAlice->SetConfigFunction("Config( \"/home/martinez/aliroot/work_NewIO/test/\" , \"box\" );"); 


============================================================
 How to run MUONCheck macro
============================================================
To check the content of a root data file, the MUONCheck
provides a ascii output on screen.

To compile MUONCheck.C
.includepath $ALICE_ROOT/STEER
.includepath $ALICE_ROOT/MUON
.L $ALICE_ROOT/MUON/MUONCheck.C++
To Load
gSystem->Load("$ALICE_ROOT/MUON/MUONCheck_C.so")

To print Kine : (default file is galice.root )
MUONkine() or MUONkine("galice.root",##) for the event number ##

To print hits : (default file is galice.root if not MUONhits("toto.root""); )
MUONhits()  or MUONhits("galice.root",##) for the event number ##

To print digits : (default file is galice.root)
MUONdigits()  or MUONdigits("galice.root",##) for the event number ##

To print rawcluster : (default file is galice.root)
MUONrecpoints() or MUONrecpoints("galice.root",##) for the event number ##

To print trigger : (default file is galice.root)
MUONTestTrigger() or MUONTestTrigger("galice.root",##) for the event number ##

....


============================================================
 How to check the Geometry
============================================================
gAlice->Init("$ALICE_ROOT/MUON/Config_MUON_test.C");
.L $ALICE/geant3/TGeant3/G3GUI.C
G3GUI()


============================================================
 How to run MUONdisplay
============================================================
First you need to perform a full simulation: 
generation, digitalisation and clusterisation
.L $ALICE_ROOT/MUON/MUONdisplay.C
MUONdisplay(0,"galice.root")

============================================================
 Tracking parameters, cuts, energy loss and physics processes
============================================================
Tracking parameters in MUON are automatically defined by GEANT
MUON takes the default values of CUTs  and physics processes
defined by the Config files, except for the gas mixture medium 
of the tracking chambers. The CUT's and physics processes of
the gas mixture medium  is then defined in the galice.cuts file
in the data directory. In particular ILOSS parameter MUST be
equal unity (1) in order simulate a realistic energy loss
distribution (mean value and fluctuations) in the active gas.

============================================================
 Tracking of particle in the magnetic field
============================================================
GEANT has two ways for tracking charged particles in the 
magnetic field: HELIX et RKUTA.
HELIX is faster and works well if the gradient of magnetic 
field is small. 
For MUON, HELIX is a not a good approximation and we must 
use RKUTA to get the optimal mass resolution of the 
spectrometer. The choice of HELIX or RKUTA is done in the
config file when the magnetic field is defined:
  AliMagFMaps* field = new AliMagFMaps("Maps","Maps", TRACKING, FACTOR, MAXB, AliMagFMaps::k4kG);
  gAlice->SetField(field);
TRACKING must be 1 for RKUTA and 2 for HELIX (the default value for aliroot is 2 (HELIX))
FACTOR allows you to set the magnetic field to 0, just putting FACTOR=0. Default value is 1.
MAXB is the maximum magnetic field which is 10.T

===========================================================
 MUON cocktail for physics ..............
===========================================================
There is a MUON cocktail generator of the muon sources in the
EVGEN directory. This class derives from AliGenCocktail.
In the init of this class I have filled the cocktail with 
the muon sources: J/Psi, Upsilon, Open Charm, Open Beauty, 
Pion, Kaons. The code needs only the production cross section 
at 4pi (for the moment this values are in the code since I 
prefere them do not be modified), and the code calculates the  
rate of particles in the acceptance, making the scaling based 
on the number of collisions for the hard probes and on the  
number of participants for soft sources: Pions and Kaons.

In the Genereate of this class all entries in the cocktail 
are called and we define a "primordial trigger" with requires 
a minimum number of muons above a Pt cut in the required acceptance.
In order to normalized to the real number of simulated events, 
there are 2 data members in the class fNsuceeded adn fNGenerate 
which tell us what is the biais source.

Enclose an example to use this generator:   
AliGenMUONCocktail * gener = new AliGenMUONCocktail();
gener->SetPtRange(1.,100.);       // Transverse momentum range  
gener->SetPhiRange(0.,360.);    // Azimuthal angle range 
gener->SetYRange(-4.0,-2.4);
gener->SetMuonPtCut(1.);
gener->SetMuonThetaCut(171.,178.);
gener->SetMuonMultiplicity(2);
gener->SetNumberOfCollisions(1950.);   
gener->SetNumberOfParticipants(400.);     
gener->SetVertexSmear(kPerTrack);  
gener->SetOrigin(0,0,0);        // Vertex position
gener->SetSigma(0,0,0.0);       // Sigma in (X,Y,Z) (cm) on IP position
gener->Init();
 
===========================================================
 csh Script for the full reconstruction with raw data generator
===========================================================


aliroot -b << EOF  
AliSimulation MuonSim("YourConfig.C")
MuonSim.SetWriteRawData("MUON");
MuonSim.Run(XXX)
.q
EOF

aliroot -b << EOF 
TPluginManager* pluginManager = gROOT->GetPluginManager();
pluginManager->AddHandler("AliReconstructor", "MUON","AliMUONReconstructor", "MUON","AliMUONReconstructor()")
AliReconstruction MuonRec("galice.root") 
MuonRec.SetRunTracking(kFALSE)
MuonRec.SetRunVertexFinder(kFALSE)
MuonRec.SetRunLocalReconstruction("MUON")
MuonRec.SetFillESD("MUON")
MuonRec.Run() 
.q
EOF

aliroot -b << EOF  
.includepath $ALICE_ROOT/STEER
.includepath $ALICE_ROOT/MUON
.L $ALICE_ROOT/MUON/MUONmassPlot_ESD.C++
MUONmassPlot("galice.root",0,99999);
.q
EOF

===========================================================
 Still working ..............
===========================================================