Raw data format

Microtracks

The raw.root files contain microtracks. Following information copied mostly from FEDRA wiki:

Run file information

Inside the run file there are following objects:

• Run file header (EdbRunHeader)

• Views tree with the data

• Fiducial marks (now obsolete, used in OPERA)

One entry into the tree is one microscope view. All data inside the view are in local View Reference System. The information about the view position in respect to stage (plate) kept in the view header.

There are the following superbranches in the Views tree:

headersGeneral information about view position and contentsclustersarray of clusters: all clusters fond in the view are heresegmentsarray of segments: all segments found in the viewtracksnot used nowframesinformation about each frame and eventually image (image usually do not saved)

View Headers branch

Header is one/view. The header object of the type EdbViewHeader:

class EdbViewHeader : public TObject {

private:

  Int_t    eViewID;   // View ID in the Area
  Int_t    eAreaID;   // Area ID in Run (prediction id)

  Float_t  eXview;    // stage coord, top left corner
  Float_t  eYview;    // 

  Float_t  eZ1;    //
  Float_t  eZ2;    // emulsion surfaces in absolute stage coordinates
  Float_t  eZ3;    // measured once per view
  Float_t  eZ4;    //

  Int_t    eNframesTop;  // top    | number of frames in the view (0,1,2...16...)
  Int_t    eNframesBot;  // bottom | 

  Int_t   eTime;         // System time since last view saving in msec

  Int_t   eNclusters;    // number of clusters saved in the view
  Int_t   eNsegments;    // number of segments saved in the view

  EdbAffine2D   eAff;    // affine transformation for the view 
                         // (make sence for SySal-converted data only)

  TArrayF  *eZlevels;    //! z of each taken view (frame) (obsolete!)

  Int_t   eCol;          // the position of the view in the scanned area, measured in views, 
  Int_t   eRow;          // starting from the reference angle (typically up-left)

  Int_t   eStatus;       // View scanning status
  Int_t eEvent           //optional: the part of the tree may be associated with event. Setted via run->header->Flag(8)
  Int_t eTrack           //optional: some view group may be associated with track. Setted via run->header->Flag(9)

Clusters branch

All clusters of the view organized as one TClonesArray of the objects type EdbCluster:

class EdbCluster : public TObject, public EdbPoint3D {

public:

  Float_t    eX;       // cluster coordinates (in microns when converted from rwd)
  Float_t    eY;       //
  Float_t    eZ;       //
  Float_t    eArea;    // Cluster area: number of pixels
  Float_t    eVolume;  // Cluster volume - in case of greyscale pixels
  Int_t      eFrame;   // frame index
  Int_t      eSide;    // emulsion side index
  Int_t      eSegment; // segment id to be attached (-1 if no segment)

Segments branch

All segments of the view organized as one TClonesArray of the objects type EdbSegment.

Note: the segments here are what we call micro-tracks!

class EdbSeg3D : public TObject {
private:
  Float_t    eX0;         // |_coordinates of the segment's initial point
  Float_t    eY0;         // | in the SAME FOR ALL SEGMENTS stage coordinate system
  Float_t    eZ0;         // |
  Float_t    eTx;         // tanX: deltaX/deltaZ
  Float_t    eTy;         // tanY: deltaY/deltaZ
  Float_t    eDz;         // length of the segment along Z with sign

//______________________________________________________________________________
class EdbSegment : public EdbSeg3D {
private:
  Int_t      eSide;       // side of the segment location (0-up, 1-down)
  Int_t      ePuls;       // puls height (number of clusters) OR (sum of clust area)*1000+(number of clusters)
  Int_t      eID;         // segment identifier
  Float_t    eSigmaX;     // dispersion parameter of grains around track line
  Float_t    eSigmaY;     // dispersion parameter of grains around track line

When data converted from Sysal rwd the eSigmaX is filled with SIGMA provided by sysal, eSigmaY in this case dummy

Frames branch

All frames of the view organized as one TObjArray of the objects type EdbFrame

Note: the frames are the images at different heights, for each xy view there are multiple frames!

class EdbFrame : public TObject {

private:

  Int_t       eFrameID;           // frame identifier
  Float_t     eZframe;            // Z-coordinate of the frame
  Int_t       eNcl;               // total number of clusters found in the frame
  Int_t       eNpix;              // total number of nonzero pixels found in the frame
  EdbImage    *eImage;            // CCD image