Π polarizability Meeting Dec 18, 2019

From GlueXWiki
Jump to: navigation, search

Meeting Info.

Meeting Time And Location

10:00 EST (JLab time)

CC L207

Connecting

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 199.48.152.152 or bjn.vc
    • Enter meeting ID above



  1. Previous meeting: Dec 11, 2019
  2. Announcements
  3. Update on Run
  4. Data Analysis - Andrew
  5. MWPC status - Rory
  6. Reference to Collaboration October Meeting
  7. Discussion of beam test (Elton, Dave, Ilya, Tim and Scot)
    1. Preliminary Analysis of TOF rates with new aperture (18x18 cm2) (Ilya)
      • These are simulated TOF trigger rate using random trigger
      • Configuration consisted of 47 um diamond radiator (coherent peak at ~ 7 GeV), 30 cm H GlueX target (3.3% r.l.), 4 DIRC bars installed.
      • Trigger rate ~30 kHz at 20 nA, ~50 kHz at 30 nA and ~80 kHz at 50 nA.
      • Notes: 1 TOF FADC not operational, which reduces the measured rates somewhat
      • This trigger should be able to be implemented with current firmware but requires a different configuration file.
    2. Discussion of proposed beam test
      • Previous estimate of TOF trigger rate was 270 kHz before TOF modification.
      • If Ilya's new rates are correct, there has been a reduction of a factor of about 270/30 ~ 9 due to the TOF new aperture and insertion of DIRC bars.
      • Ilya is checking his calculations. If confirmed, it is proposed to measure rates without the DIRC bars.
      • Removal (insertion) of DIRC bars is a shift. Tim believes this can be done with the magnetic field on.
      • So this test could be accomplished with a setup shift, one data shift, and one restore shift.
    3. Hardware Preparations
      • It was decided to go ahead and enlarge the hole in the existing lead sheets in case they might be needed. They will be enlarged to 17.5x17.5 cm2 to match the TOF 18x18 cm2 aperture.
    4. CPP Design
      • Tim will setup a design meeting in Jan to review specifications for the CPP muon detector.
  8. Simulation Tasks:
    • Geometry in HDDS
    • MWPC hits in hdgeant4
    • Absorber thicknesses study
    • Target position study
    • Trigger acceptance study
    • other?
  9. Other business
  10. Next meeting