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2 How to run MUONRecoCheck macro
3============================================================
4
5To check the muon reconstruction by comparing the reconstructed tracks
6with the reference tracks made of "AliTrackReference" for the hits in chamber (0..9)
7and kinematic informations (TreeK) for the vertex.
8This macro can be used to check the track reconstruction e.g. efficiency,
9momentum resolution ... but also to make physics analysis whenever
10track identification is needed.
11
12To compile MUONRecoCheck.C
13.includepath $ALICE_ROOT/STEER
14.includepath $ALICE_ROOT/MUON
15.L $ALICE_ROOT/MUON/MUONRecoCheck.C+
16
17// To run MUONRecoCheck
18MUONRecoCheck(nEvent,"geometry.root", "galice.root"); // nEvent = nb of events
19
20
21==========================================================
22Macros for MC studies
23==========================================================
24
25For MC studies the classes "AliMUONTrackLight" and "AliMUONPairLight" can be
26used in order to fill not only the single muon / dimuon's kinematics (charge,
27pT, rapidity, etc) at the generation AND reconstruction level, but also for
28"decoding" the Pythia output and for the storing of the single muon's history.
29This allows to tag if two muons of a given event come from a certain, well-defined
30process, such as J/psi, Upsilons, correlated open charm or open beauty or the
31low masses or if they are of uncorrelated origin. For open beauty/charm it also
32tags the creation process (pair creation, flavour excitation or gluon splitting).
33The classes also allow to tag feed-down or neutral B meson oscillation and
34has a method that checks whether the reconstructed track is a muon or not.
35
36The macros ReadRecoCocktail.C, DecodeRecoCocktail.C and MergeMuonLight.C
37are examples how to use these two classes. DecodeRecoCocktail.C opens the
38generated files, loops over the events and fills an AliMUONTrackLight object
39for every reconstructed track for which the reference to its generated particle
40could be established, using the AliMUONRecoCheck class.
41It then takes the AliMUONTrackLight objects and forms - event by event -
42AliMUONPairLight objects, on a combinatorial basis. For a given event these
43objects are stored in respective TClonesArrays which are then stored in a tree.
44By default, the produced output file is called "MuonLight.root".
45This root file can then be taken by the macro "ReadRecoCocktail.C" that shows,
46on the example of the reconstructed mass and pT of the AliMUONPairLight object,
47how to access the available information. For large statistics, in which many
48individual MuonLight.root files are produced, MergeMuonLight.C can be used
49to merge the files and produce one common output root file.
50
51To read a generation/reconstrution from PDC06 preproduction, and write a file
52with a tree of AliMUONTrackLight / AliMUONPairLight :
53go to the directory containing the generation/reconstruction. From there run
54aliroot
55.L DecodeRecoCocktail.C+
56DecodeRecoCocktail();
57.q
58
59To read the file previously generated:
60aliroot
61.L ReadRecoCocktail.C+
62ReadRecoCocktail();
63.q