GlueX Level-3 Trigger Meeting, May 19, 2016

From GlueXWiki
Jump to: navigation, search

Meeting Info.

Meeting Time And Location

16:00 EST (JLab time)

CC A110


You can connect using BlueJeans Video conferencing (ID: 949 429 419). (Click "Expand" to the right for details -->):

  1. Make sure you have created a BlueJeans account via your JLab CUE account using this link:

  2. Meeting ID: 949 429 419
    • (you may need to type this in, depending how you connect)

  3. If connecting via Web Browser: click this link (no passcode is needed):

  4. If connecting via iOS or Android App:
    • Use your JLab e-mail address to log in and then enter the meeting ID given above to join the meeting

  5. If connecting via Phone: Dial one of the following numbers and then enter the meeting ID above and hit "#" or "##"

  6. If connecting via Polycom unit:
    • Dial or
    • Enter meeting ID above


This is initial meeting will be organizational.

Informational Links:

Justin's collaboration meeting talks:


Attendees: David L., Adesh S., Justin S., Mike W., Cristiano F.


  • L3 is not a requirement for the Fall 2016 and Spring 2017 runs. We will schedule some commissioning time during these runs
  • Current schedule has no Hall-D running in Fall 2017
  • Expect to have fully deployed L3 system in use for Fall 2018 run


  • Primary goal of L3 is to reduce/eliminate events with Eγ < 7GeV
  • Justin briefly reviewed his slides from Oct. 2014 GlueX collaboration meeting to remind us what has been done and where we left it
  • Plan is to implement MVA (=multivariate analysis) with focus on BDT
    • We will start with the TMVA package that is integrated into ROOT
    • May eventually move to other algorithms developed specifically for this type of triggering
  • Two approaches:
    1. Detailed Monte Carlo where all truth information is available
    2. Real data from Spring 2016 run where events can be flagged as "reconstructable"
    • Both will be pursued. Simulation will necessarily need to improve to meet physics goals of GlueX and L3 will benefit from that
  • Simulated data set being generated for GlueX ("sim1") will not be sufficient for L3 study since it has a lower bound of Eγ = 4GeV. We will need to generate another with energies down to π threshold
    • L3 simulated data set will match the conditions of the "first priority" data as determined by Analysis Working Group. Specifically, runs 11347-11555 (see here for details)
    • Adesh will put together wiki page with simulation specifications and status
  • Mike noted that another important piece of information will be the CPU cost of various algorithms that may be used as input to the BDT
    • Cristiano will start looking at this and documenting it.
    • This may prompt some optimizations of code where L3 would benefit so the benchmarking tools developed are expected to be reused multiple times
    • Some preliminary work in this area was shown at the May Collab. Meeting

Future Meetings

  • We will have future meetings bi-weekly on Fridays at 11:00am. This is the same time as the bi-weekly DIRC meetings but out of phase by a week to make it convenient for those who attend both meetings
  • Next meeting will be Friday May 27