Pion Meeting July 9 2021 11AM ET

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Agenda

  1. Updates on pion detector studies (Elham) [1]
  2. Beam generator simulations (Raj)

Attendance

David, Elham, Jim, Julia, Raj, Wouter

Minutes

  • Pion detector studies (David)
    • Rate weighting does not make a difference [2]
    • Light into lucite comes from corners, and reducing lucite size increases pi/e ratio by about factor of two [3]
  • Pion detector studies (Elham)
    • Changing angles of lead donut or phi acceptance of lucite doesn't affect pi/e ratio much [4]
      • pions illuminate front face of lucite uniformly, significant reduction of high energy electrons
      • why are there so many photoelectrons from low energy electrons and why is it independent of lucite size?
        • TODO: which events cause most photoelectrons?
          • plot the position of events in lucite 8001 for events which have number of photoelectrons in 8000 above a certain threshold
          • plot the number of photoelectrons in 8000 for events which have a momentum in lucite 8001 above versus below 2 MeV
          • define low-energy for electrons as the ones that are below 2 MeV but ALSO above Cerenkov threshold
  • Pion detector studies II (David)
    • Showermax leakage [5]
      • primary electrons lose 3.5 GeV in showermax, but leakage primary electrons lose a lot less
      • most electrons that cause leakage are at sin(phi) = 0.06 or ~3.4 degrees
      • some electrons generated at small angles, not sure where they come from
    • Primaries exiting showermax [6]
  • Pion detector studies II (Elham)
    • Tilted showermax [7]
      • Pions shouldn't change since they don't care about showermax, so likely factor 10 division needed
      • High energy pions unchanged, high energy electrons reduced by factor 2
      • Low energy pions statistically zero, low energy electrons reduced slightly
      • TODO:
        • Repeat with 5M events to avoid having inconsistent rate conversions
        • Produce wavelength spectrum of photoelectrons for high/low energy electrons/pions
        • Double check if lucite has scintillation enabled
    • Thick aluminum plate [8]
      • Why again factor 10 different?
        • scaling factor for 'rate' only needed if number of simulation files is changed, not when number of simulated events per file is changed
      • TODO:
        • Repeat with 5M events to avoid having inconsistent rate conversions
        • Repeat with 5M events for plate with 48" diameter hole (assuming no overlaps)
  • Summary
    • Tilting showermax makes things slightly better -> let Dustin McNulty know
    • Plate with hole is workable -> let Dave Kashy know
    • Donuts with non-tapered outside may be sufficient
    • TODO:
      • Move showermax out radially by a cm (for testing purposes, see if this cuts the leakage electrons)
      • Look at photoelectron energy spectrum and think about energy cut on optical photons < 5eV
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