Reconstruction, May 19, 2009

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Time: 11:00 EST/10:00 CST

  • Connection: EVO: Room Booked under the GlueX Universe, called Reconstruction Meeting
  • Backup Plan: ESNET Number 8542553

Reconstruction To Do List

  1. Generation
    1. Use genr8 for a2 production
    2. Skim off (hd_filter) the wanted events by cutting on the total neutral energy (> 6 GeV) but record the total number of events before skimming. The resulting MC data set will be stored for general use.
    3. Use Pythia for background generation after removing a2 → η π0 from the MC data stream
    4. Use a2 charge exchange production xsection vs pythia total xsection to estimate number of signal and noise events
  2. Analysis
    1. After pruning the Pythia events, check the generated vs. reconstructed energy in a plot.
    2. Look at the a2 mass peak - adjust cuts on the eta and pi0 masses then look at the effect on the different angular distributions (i.e. Gottfried-Jackson angles, etc.)
    3. look at difference between reconstructed and generated z position for less than 65 cm
    4. look at single photon reconstruction efficiencies
    5. adjust the error matrix for the BCAL (look in PID/DPhoton_factory.cc)
  3. Gather all relevant DocDB documents and cross section publications at one spot on the Wiki.

Documents to Review

Tentative Agenda

  1. Test EVO connection
  2. Review Reconstruction Plans in list above
  3. a2 cross section papers
  4. Discussion
  5. Blake's trip to Indiana

Minutes

Attendees: Matt, Mihajlo, Jake (IU), Blake, Zisis (Regina)

  1. EVO connection: We ran the meeting under EVO. IU connected via their H.323 Polycom and Regina ran EVO on Zisis' iMac desktop. We were not too happy with the sound and there was a big lag between picture and sound. After the meeting Blake recommended using Ventrilo for sound. we will try this out next week.
  2. Review Reconstruction Plans: Matt suggested reordering some of the steps, so that the MC data set created is initially of general use before being pruned further to exclude the ηπ channel. Ths list has been updated above.
  3. a2 cross section papers: Blake and Zisis are going through these to pick out information useful to our simulations. One paper gave the negatively charged a2 production as 0.45 μb and Pythia has 124 μb total cross section. These number will be used in deciding how many events to run in the signal and background channels.
  4. Discussion: Blake will contact Eugene and Richard to ask details about the use of bggen vs Pythia, and specifically how to implement random seed in the latter and how are cross sections handled below 3 GeV in the former (Pythia is called by bggen only above 3 GeV).
  5. Blake's trip to Indiana: Week of June 22.
  6. Other business: Matt reported that Jake will work on ρ π channels going to π+π+π- and π+π0π0 and using isospin relations. This work will complement Blake's neutral channels.