|
BrModuleMatchTrackclass description - source file - inheritance tree class BrModuleMatchTrack : public BrModule
private:
Data Members
private:
Class DescriptionThe BrModuleMatchTrack class provides an interface to the BRAHMS Tracking Combining of two detectors with a magnet in between. It is a general module combining any two tracking detectors surrounding a single dipole. eg. TPM1-D5-TPM2 or T1-D2-T2 At present the module assumes the effective edge approximation for the magnetic field. Initial track matching is done base on 3 cut parameters, namely All the following cuts are sigmas in the variable. The actual cut in done in MatchesCuts(dang, dy, daly, p) SigmaMatchedDang : cut for difference in signed angle between tracks alpah1-alpha2. Good tracks have DAlpha=0. This cut is momentum and particle dependent. SigmaMatchedDy : cut for vertical position difference on effective midplane. SigmaMatchedDaly : cut for vertical slope difference (take as dy/dz for track front and back of magnet. SigmaRange: The actual cut is SigmaRange*Sigmaparameter. MatchDyOffset : Quite often small offset are present in the tracking matching. This is introduced in order to make symmetric cuts. The parameter is only used when checking for the cuts limits. The calculations of tracks are now done in relative coordinates, and not in global as before. This implies changes for the members of the content of BrMatchedTrack. Char_t* GetSourceVersion() const BrModuleMatchTrack() : BrModule() Default Constructor. Do not use - Is only here for the purpose of various ROOT functionality. BrModuleMatchTrack(const Char_t *Name, const Char_t *Title) : BrModule(Name,Title) Set volume parameters to null, Create clones arrays for internal use Read simulation parameters from default file (simpar.dat) in current directory BrModuleMatchTrack(const Char_t *Name, const Char_t *Title, const Char_t *tfront, const Char_t *tback, const Char_t* tmagnet) : BrModule(Name,Title) Constructor; Setup module. Get volume parameters from BrGeometryDbManager. This removes any need for the application to deal with the geometry. This module do not need to know where the Db information comes from. Please note that the geometry db objects are owned by the Geometry Manager and MUST not be deleted by the module. Create clones arrays for internal use Set default matching parameters. void Init() void DefineHistograms() define diagnostics histograms for track combination module Book histograms (called from BrModule::Book) void SetDefaultParameters() Set/Reset internal tracking parameters, cuts to default values. void CreateClonesArrays() Create the clones arrays used for internal structures. void Clear() Clear event structures. void ClearClonesArrays() Clear the clones arrays used for internal structures. ~BrModuleMatchTrack() Destructor void Event(BrEventNode* InputNode, BrEventNode* OutputNode) Normal Event Method for BrModule. The local detectortracks for the front and back chamber must be found in the InputNode. If matching is succesfull a table of BrMatchedTrack are added are added to Outputnode as well as a table for void CombineFrontBack(BrEventNode *InputNode) Loop over tracks in TFront / TBack and see how well they match and create candidates for tracks This algorithm is the effective edge. For tracks matched they are added to the Clones array for matched BrTracksFrontBack (i.e. front back) Bool_t GetFiducialStatus(BrDetectorTrack* front,BrDetectorTrack* back) This method provides fiducial cuts base on BrMagnetVolume::GetSwimStatus void Finish() Finish Summarize performance void CleanUpTracks() This cleanup method calls the two methods: CleanUpSharedBackTracks() and CleanUpSharedFrontTracks() CleanUpSharedBackTracks() finds mathced tracks that shares back tracks, find the best by looking at overall chisq in matching parameter, and set the status of the tracks (kOk for the best one, ...) - this is the old CleanUpTracks() method. CleanUpSharedFrontTracks() does the same as CleanUpSharedBackTracks() just for the front tracks. The only difference is that this method checks that the status is kOk before it compares the front tracks. void CleanUpSharedBackTracks()
The cleanup process implemented here is reasonably simple
and incorporates the ideas used in the first analysis of
the 2000 MRS data. The initial matching applies rather
wide cuts in matching tracks. It can therefor well happen
that e.g. the same backtrack is matched up with more than one
front track. This happened in about 2-5% of the cases. The present
algorithm sorts those out, or rather set the status after having selected
the better one.
The check for vertex cuts are not done here. It was deemed better to
do so in a specific filter module.
a) Identify tracks tracks that have multiple usage
b) Identify best tracks by looking at overall chisq in matching
parameter.
c) at this time an overall estimat based on cut parameters and
fidicual cuts are done.
void CleanUpSharedFrontTracks() void ListMatchingParameters() const Bool_t MatchesCuts(Double_t dang, Double_t dy, Double_t daly, Double_t p) Function to check if a matching fit is found between calculated parameters for deviate in angle, y and slopes. The (estimated) momentum is also a parameter to allow for better criteri with time. The cuts are detector, magnet and momentum dependent due to multiple scattering and detector resolution. The offset evaluation is applied here, as the only place in the code. void Print(Option_t* option) const Print info on module Inline Functions
void SetNtuple(Bool_t n = kFALSE)
TClonesArray* GetMatchedTracks() const
BrDetectorVolume* GetFrontVolume() const
BrDetectorVolume* GetBackVolume() const
BrMagnetVolume* GetMagnetVolume() const
void SetMatchDangOffset(Double_t value)
void SetMatchDalyOffset(Double_t value)
void SetMatchDyOffset(Double_t value)
void SetFiducialCutDx(Double_t value)
void SetFiducialCutDy(Double_t value)
Double_t GetSigmaDang() const
Double_t GetSigmaDaly() const
Double_t GetSigmaDy() const
Double_t GetMatchDangOffset() const
Double_t GetMatchDalyOffset() const
Double_t GetMatchDyOffset() const
Double_t GetSigmaRange() const
Double_t GetSigmaCut() const
Double_t GetFiducialCutDx() const
Double_t GetFiducialCutDy() const
void SetSigmaDang(Double_t val)
void SetSigmaDaly(Double_t val)
void SetSigmaDy(Double_t val)
void SetSigmaRange(Double_t val)
void SetSigmaCut(Double_t val)
void SetRotationFactors(Double_t f = 1.0, Double_t b = 1.0)
void SetHistMomentumRange(Double_t range = 20.0)
void SetOldFiducialCuts()
Char_t* GetHeaderVersion() const
TClass* Class()
TClass* IsA() const
void ShowMembers(TMemberInspector& insp, char* parent)
void Streamer(TBuffer& b)
void StreamerNVirtual(TBuffer& b)
BrModuleMatchTrack BrModuleMatchTrack(BrModuleMatchTrack&)
|
||||||
|
This page automatically generated by script docBrat by Christian Holm |
Copyright ; 2002 BRAHMS Collaboration
<brahmlib@rcf.rhic.bnl.gov>
|