Mattione Update 09072011

FCAL Reconstruction

• The reconstructed FCAL time is significantly offset from the simulated times.

• hd_dump of DFCALShower, DFCALTruthShower, and DFCALHit. Note that both the DFCALShower and DFCALHit times are ~2+ ns greater than the DFCALTruthShower times.

Event: 1
DFCALShower:
 E(GeV):   X(cm):   Y(cm):   Z(cm):   t(ns):
--------------------------------------------
   3.27    -8.27    63.70   642.36    21.16  //Photon generated at target center (0, 0, 65), so path length = 580.922 and t should be = 19.377

DFCALTruthShower:
 x(cm): y(cm): z(cm): px(MeV/c): py(MeV/c): pz(MeV/c):   E(MeV): t(ns): primary: track: type:
---------------------------------------------------------------------------------------------
  -8.0   61.7  625.3      -44.8      343.8     3123.6  3142.732   18.8        1      1     1  //Photon generated at target center (0, 0, 65), so path length = 563.744 and t should be = 18.8
//similar, additional hits were present but were truncated

DFCALHit:
  row: column: x(cm): y(cm):   E(MeV):  t(ns):
----------------------------------------------
   44      26  -12.0   60.0    42.050  21.082 
//similar, additional hits were present but were truncated

• In programs/Simulation/HDGeant/hitFCal.c the times saved to the s_FcalTruthShowers_t and s_FcalTruthHit_t objects (line ~172) are different: the s_FcalTruthHit_t times (which are later smeared and converted to DFCALHit objects) are increased to account for what looks like the light propagation in the calorimeter. However, I'm not sure that this is taken into account in the DFCALCluster reconstruction code. I'm not really familiar with it though, so I'm hoping that someone who is will take a look at this.