Difference between revisions of "Reconstruction Tasks and Topics for Further Development"

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__TOC__
 
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== Mark's Draft List ==
 
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The items listed here are areas that we have identified as needing further development and/or study. Feel free to add your topics or comment on those already listed. Comments can be entered on the "discussion" tab (see above).
 
  
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# Particle identification
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= Focus Areas =
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## What is the general scheme (or schemes) that we want to support?
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## What is the nature of the user interface into particle ID information?
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We will try to broadly classify outstanding software issues and tasks into three focus areas:  Tracking, Calorimetry, and PID.  For each of these areas we have appointed a contact person:  Simon (Tracking), Matt (Calorimetry), and Paul (PID).  The contact person is responsible for both prioritizing the issues to work on, seeing that progress is made on resolving these problems, and reporting status at each software meeting.
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# &chi;<sup>2</sup> distributions from track fits
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## What are the main causes of tracks in the zero probability peak?
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## Are hit reconstruction errors calculated correctly? Consistently?
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== Tracking ==
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# Re-do checks of error matrices from photon reconstruction
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=== Issues to Resolve ===
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# wrong track sign choice at pattern recognition stage in FDC
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# poor proton reconstruction in b<sub>1</sub>&pi; events
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## ...in general, need to improve tracking efficiency for multi-particle events...
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# incorrect &chi;<sup>2</sup> distributions from track fits:  huge peak at zero
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# validate propagation of errors from hit level through the fitting procedure to the track level
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=== Questions to Answer ===
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# How do we handle large single Coulomb scattering in tracking, e.g. between the CDC and FDC?
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# How do we handle decays in tracking? (This might have similar resolution to the question above since the track shape is similar.)
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# Can we quantify the performance of the track finding algorithm in a variety of event environments?
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== Calorimetry ==
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=== Issues to Resolve ===
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# allow easy switch between 1-2-3-4 and 3-3-4 BCAL schemes; include calibrations for both
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# tune new BCAL reconstruction algorithm, explore impact on shower multiplicity in b<sub>1</sub>&pi; events
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# include timing reconstruction in FCAL
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# correct the error matrix calculation for both FCAL and BCAL
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=== Questions to Answer===
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# When photons get split into multiple clusters, is all of the energy detected?
 
# When photons get split into multiple clusters, is all of the energy detected?
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# How do we handle large single Coulomb scattering in tracking?
 
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# How do we handle decays in tracking?
 
 
# What is our efficiency for &pi;<sup>0</sup> detection? &eta;&rarr;&gamma;&gamma;?
 
# What is our efficiency for &pi;<sup>0</sup> detection? &eta;&rarr;&gamma;&gamma;?
  
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== Comments from Curtis ==
 
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This looks like a good list. I might suggest that it be reworked a bit. In particular, we have three broad topics with issues:
 
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# tracking
 
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# photon reconstruction
 
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# particle identification.
 
  
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With regard to (1), the problems manifest themselves as large chi-squares from tracking and the tracking errors being problematic in a way that cannot be systematically corrected. I would guess that these are correlated with underlying issues in:
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== PID ==
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# pattern recognition where incorrect hits are used.
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# large scattering in material between CDC and FDC.
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# possible errors in the fitting procedure itself.
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# other as yet unknown causes.
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I think that the only way that we are going to make progress here is to go systematically through the code and try to identify problems and fix them. I believe that Simon, Paul M. and possibly Kei after the beam tests.
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With regard to (2), my feeling from our b1-pi studies is that this is coupled to the BCAL reconstruction. In this case, the big improvements will hopefully come from tuning the algorithm in the the existing code. However, there are some caveats.
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=== Tasks/Issues to Resolve ===
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# The BCAL readout segmentation will affect this. We need to settle this asap, or move forward under the 1-2-3-4 assumption.
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# Once segmentation is settled, we can go back and tweak the parameters in the BCAL code.
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In this case, Matt updated code which is checked in and Will L. is now looking at it. Modulo (i) being decided, I hope that we can move forward fairly quickly here.
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Finally, for (3), this is a higher level issue that will ultimately require (1) and (2) to be improved.Your posed questions put this in the light more of discussion, rather than underlying software issues. While it may lead to issues as we move forward on the above, it is hard to say at the moment.
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# Develop neutron reconstruction: calculate neutron energy from energy in calorimeters.  
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For progress, Paul M. is going through the code looking at the inputs to the PID and trying to make sure that they make sense.
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# Improve TOF/BCAL/FCAL uncertainties and integrate into PID. 
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# Implement TOF dE/dx calculation and integrate into PID.
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# Look into implementing BCAL dE/dx calculation.

Latest revision as of 15:14, 4 October 2011

Focus Areas

We will try to broadly classify outstanding software issues and tasks into three focus areas: Tracking, Calorimetry, and PID. For each of these areas we have appointed a contact person: Simon (Tracking), Matt (Calorimetry), and Paul (PID). The contact person is responsible for both prioritizing the issues to work on, seeing that progress is made on resolving these problems, and reporting status at each software meeting.


Tracking

Issues to Resolve

  1. wrong track sign choice at pattern recognition stage in FDC
  2. poor proton reconstruction in b1π events
    1. ...in general, need to improve tracking efficiency for multi-particle events...
  3. incorrect χ2 distributions from track fits: huge peak at zero
  4. validate propagation of errors from hit level through the fitting procedure to the track level

Questions to Answer

  1. How do we handle large single Coulomb scattering in tracking, e.g. between the CDC and FDC?
  2. How do we handle decays in tracking? (This might have similar resolution to the question above since the track shape is similar.)
  3. Can we quantify the performance of the track finding algorithm in a variety of event environments?

Calorimetry

Issues to Resolve

  1. allow easy switch between 1-2-3-4 and 3-3-4 BCAL schemes; include calibrations for both
  2. tune new BCAL reconstruction algorithm, explore impact on shower multiplicity in b1π events
  3. include timing reconstruction in FCAL
  4. correct the error matrix calculation for both FCAL and BCAL

Questions to Answer

  1. When photons get split into multiple clusters, is all of the energy detected?
  2. What is our efficiency for π0 detection? η→γγ?


PID

Tasks/Issues to Resolve

  1. Develop neutron reconstruction: calculate neutron energy from energy in calorimeters.
  2. Improve TOF/BCAL/FCAL uncertainties and integrate into PID.
  3. Implement TOF dE/dx calculation and integrate into PID.
  4. Look into implementing BCAL dE/dx calculation.
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