Difference between revisions of "BCAL Reconstruction Issues"

From GlueXWiki
Jump to: navigation, search
 
(21 intermediate revisions by 2 users not shown)
Line 1: Line 1:
* Simulation (mcsmear)
+
# '''BDT Work'''
** fADC timing
+
#* Implement truth information; improve rejection of and understand origin of 'bad clusters'
*** Uses threshold crossing time rather than FPGA-ish algorithm
+
# '''Simulation (mcsmear)'''
*** Resolution is too poor
+
#* fADC timing: Resolution is too poor
** mcsmear doesn't seem to smear data enough
+
#* mcsmear doesn't seem to smear data enough
*** TDC timing resolution is too good
+
#** TDC timing resolution is too good
*** single photo-electron peaks in energy spectrum
+
#** single photo-electron peaks in energy spectrum
** spikes in time histogram at low energy
+
#** spikes in time histogram at low energy
** max ADC amplitude (12 bits?)
+
#* Very low energy ADC hits coming from mcsmear
** Sampling fluctuations not applied on per-particle basis
+
#* Bulk attenuation length vs short and long components (get atten length from ccdb)
* Timewalk corrections
+
# '''DBCALPoint''' (reconstructing E,z,t from double-ended hit)
** Establish procedure for doing these corrections based on simulated data (how closely should this match the correction procedure for real data?)
+
#* When determining energy, give more weight to higher energy hit? (also in averaging time?)
** Determine form of timewalk corrections
+
#* Best way to determine sigma_z?
** What if we have TDC info only on one end?
+
#* How to deal with multiple hits in same channel?
* DBCALPoint (reconstructing E,z,t from double-ended hit)
+
# '''Clustering'''
** When determining energy, give more weight to higher energy hit? (also in averaging time?)
+
#* Use only timing information from fADCs?
** Best way to determine sigma_z?
+
#** If we use TDC info also, we need to appropriately make use of the different timing errors of different hits
** How to deal with multiple hits in same channel?
+
#* Determining cluster properties (E, x, y, z, t)
* Clustering
+
#* How to average cell-by-cell position to get cluster position
** Use only timing information from fADCs?
+
#** Weight averages by...? E? E^2? 1/sigma^2?
*** If we use TDC info also, we need to appropriately make use of the different timing errors of different hits
+
#** Average rectangular coordinates? Cylindrical? Spherical?
 +
#* Energy corrections (z-dependent, non-linear)
 +
#** Is current scheme good enough?
 +
#** If so, write a plugin to automate this process.
 +
#** Need extra special treatment of ends of calorimeter?
 +
#* How to determine errors (and correlations) on cluster properties (important for kinematic fitting)
 +
# '''Matching with tracks:''' get update from Simon/Paul
 +
# '''Timewalk corrections'''
 +
#* Establish procedure for doing these corrections based on simulated data (how closely should this match the correction procedure for real data?)
 +
#* Determine form of timewalk corrections
 +
#* What if we have TDC info only on one end?

Latest revision as of 15:47, 13 January 2015

  1. BDT Work
    • Implement truth information; improve rejection of and understand origin of 'bad clusters'
  2. Simulation (mcsmear)
    • fADC timing: Resolution is too poor
    • mcsmear doesn't seem to smear data enough
      • TDC timing resolution is too good
      • single photo-electron peaks in energy spectrum
      • spikes in time histogram at low energy
    • Very low energy ADC hits coming from mcsmear
    • Bulk attenuation length vs short and long components (get atten length from ccdb)
  3. DBCALPoint (reconstructing E,z,t from double-ended hit)
    • When determining energy, give more weight to higher energy hit? (also in averaging time?)
    • Best way to determine sigma_z?
    • How to deal with multiple hits in same channel?
  4. Clustering
    • Use only timing information from fADCs?
      • If we use TDC info also, we need to appropriately make use of the different timing errors of different hits
    • Determining cluster properties (E, x, y, z, t)
    • How to average cell-by-cell position to get cluster position
      • Weight averages by...? E? E^2? 1/sigma^2?
      • Average rectangular coordinates? Cylindrical? Spherical?
    • Energy corrections (z-dependent, non-linear)
      • Is current scheme good enough?
      • If so, write a plugin to automate this process.
      • Need extra special treatment of ends of calorimeter?
    • How to determine errors (and correlations) on cluster properties (important for kinematic fitting)
  5. Matching with tracks: get update from Simon/Paul
  6. Timewalk corrections
    • Establish procedure for doing these corrections based on simulated data (how closely should this match the correction procedure for real data?)
    • Determine form of timewalk corrections
    • What if we have TDC info only on one end?