z scan, run 420

Performance and calibration studies for run 420.

  • CERN 18
  • S420, bar with 3-layer spherical lens
  • protons @ 7 GeV/c
  • geometrical reconstruction
  • delta t selection with s = 0.5 ns

Geant visualization of two extreme positions. z=250 mm:

z=850 mm:

Position calibration for the lens by scanning x-step (steps definitions) Show/Hide

For y-step:

=>lens's steps: [65,18.5] mm

Azhimuthal scan for z = 650 mm Show/Hide

Time difference cut scan (for bugged version) Show/Hide

Chromatic correction Show/Hide

before correction (beam data z = 850 mm):

after correction:

performance conparision:

Performance plots after all corrections (0.5 ns time constant cut) Show/Hide

Simulation with Ideal path in EV Show/Hide

all pathes:

Direct vs. reflected photon yield Show/Hide

0.5 ns time constant cut:

1.5 ns time constant cut:

comparision with simulation without transport efficiency (1.5 ns):